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.

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:xx-xx.].

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.

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.

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.

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.

Degenerative Peripheral Retinoschisis: Observations From Ultra-Widefield Fundus Imaging

BACKGROUND AND OBJECTIVE

To describe the ultra-widefield (UWF) imaging characteristics of patients with degenerative peripheral retinoschisis (DPR) using Optomap technology.

PATIENTS AND METHODS

In this multicenter, retrospective, noncomparative, consecutive case series, eligible patients underwent detailed retinal examination including indirect ophthalmoscopy. UWF fundus imaging, including color fundus photography, autofluorescence, and angiography, was performed using standardized protocols and findings were recorded and reviewed and analyzed.

RESULTS

A total of 35 patients (58 eyes) with DPR were identified who underwent 55 sessions of UWF imaging. Mean age was 65 years, and the inferotemporal quadrant was most commonly affected (74% of eyes). Of these patients, 31 underwent fluorescein angiography and 90% of these studies illustrated abnormalities in the area affected by the schisis. The most common finding was retinal vascular leakage originating from the deep capillary plexus observed in 29 eyes (93.5%).

CONCLUSIONS

UWF imaging enables a more detailed identification of the clinical features associated with DPR and provides simple, practical, and noninvasive tools to monitor progression of disease. The breadth of retinal vascular complications identified with fluorescein angiography may suggest an important vascular component associated with the pathogenesis of this entity. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:557-564.].

Scleral Transillumination With Digital Heads-Up Display: A Novel Technique for Visualization During Vitrectomy Surgery

BACKGROUND AND OBJECTIVE

To describe a novel technique of scleral indentation and transillumination for single-surgeon, unassisted vitrectomy and vitreous base shaving enhanced with a digital heads-up display system (NGENUITY 3D Visualization System; Alcon, Fort Worth, TX).

PATIENTS AND METHODS

This technique was utilized in six eyes of six patients during vitrectomy surgery for common vitreoretinal surgical diagnoses. In each case, the transillumination was performed with the traditional intraocular light pipe set at 100% power, placed obliquely just posterior to the vitreous base insertion, with or without a transillumination adapter. The visualization of the vitreous cavity was digitally enhanced using a heads-up display system (NGENUITY 3D) with light amplification settings increased to near-maximal gain. In each case, the adequacy of the surgical view was judged intraoperatively by two independent surgeons who shared the same surgical view as the primary surgeon.

RESULTS

In this series, the surgical view provided by the scleral transillumination was deemed adequate to safely perform surgery in five of six cases. In the one patient in whom this was not the case, vitrectomy was completed using traditional endo-illumination and scleral depression performed by a skilled assistant. Lighter fundus pigmentation, myopia, thin sclera, and absence of dense peripheral media opacities were associated with improved view with scleral transillumination. There were no intraoperative complications.

CONCLUSION

Digitally enhanced scleral transillumination affords surgeons another option for safe and effective simultaneous scleral depression and illumination for unassisted peripheral vitrectomy. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:436-439.].

Correlating Changes in the Macular Microvasculature and Capillary Network to Peripheral Vascular Pathologic Features in Familial Exudative Vitreoretinopathy

PURPOSE

To evaluate the macular microvasculature in patients with familial exudative vitreoretinopathy (FEVR) using OCT angiography (OCTA) and to assess for peripheral vascular changes using widefield fluorescein angiography (WFA).

DESIGN

Multicenter, retrospective, comparative, observational case series.

PARTICIPANTS

We identified 411 patients with FEVR, examined between September 2014 and June 2018. Fifty-seven patients with FEVR and 60 healthy controls had OCTA images of sufficient quality for analysis.

METHODS

Custom software was used to assess for layer-specific, quantitative changes in vascular density and morphologic features on OCTA by way of vessel density (VD), skeletal density (SD), fractal dimension (FD), vessel diameter index (VDI), and foveal avascular zone (FAZ). Widefield fluorescein angiography images were reviewed for peripheral vascular changes including capillary dropout, late-phase angiographic posterior and peripheral vascular leakage (LAPPEL), vascular dragging, venous-venous shunts, and arteriovenous shunts.

MAIN OUTCOME MEASURES

Macular microvascular parameters on OCTA and peripheral angiographic findings on WFA.

RESULTS

OCT angiography analysis of 117 patients (187 eyes; 92 FEVR patients and 95 control participants) demonstrated significantly reduced VD, SD, and FD and greater VDI in patients with FEVR compared with controls in the nonsegmented retina, superficial retinal layer (SRL), and deep retinal layer (DRL). The FAZ was larger compared with that in control eyes in the DRL (P < 0.0001), but not the SRL (P = 0.52). Subanalysis by FEVR stage showed the same microvascular changes compared with controls for all parameters. Widefield fluorescein angiography analysis of 95 eyes (53 patients) with FEVR demonstrated capillary nonperfusion in all eyes: 47 eyes (49.5%) showed LAPPEL, 32 eyes (33.7%) showed vascular dragging, 30 eyes (31.6%) had venous-venous shunts, and 33 eyes (34.7%) had arteriovenous shunts. Decreasing macular VD on OCTA correlated with increasing peripheral capillary nonperfusion on WFA. Decreasing fractal dimension on OCTA correlated with increasing LAPPEL severity on WFA.

CONCLUSIONS

Patients with FEVR demonstrated abnormalities in the macular microvasculature and capillary network, in addition to the peripheral retina. The macular microvascular parameters on OCTA may serve as biomarkers of changes in the retinal periphery on WFA.

The Impact of Prefilled Syringes on Endophthalmitis Following Intravitreal Injection of Ranibizumab

PURPOSE

To compare the rates of infectious endophthalmitis following intravitreal injection of ranibizumab using prefilled syringes vs conventional preparation.

DESIGN

Multicenter retrospective cohort study.

METHODS

All eyes receiving intravitreal injection of 0.5 mg ranibizumab for retinal vascular diseases at 10 retina practices across the United States (2016 to 2017) and Japan (2009 to 2017) were included. The total numbers of eyes and injections were determined from billing codes. Endophthalmitis cases were determined from billing records and evaluated with chart review. Primary outcome was the rate of postinjection acute endophthalmitis. Secondary outcomes were visual acuity and microbial spectrum.

RESULTS

A total of 243 754 intravitreal 0.5 mg ranibizumab injections (165 347 conventional and 78 407 prefilled) were administered to 43 132 unique patients during the study period. In the conventional ranibizumab group, a total of 43 cases of suspected endophthalmitis occurred (0.026%; 1 in 3845 injections) and 22 cases of culture-positive endophthalmitis occurred (0.013%; 1 in 7516 injections). In the prefilled ranibizumab group, 12 cases of suspected endophthalmitis occurred (0.015%; 1 in 6534 injections) and 2 cases of culture-positive endophthalmitis occurred (0.0026%; 1 in 39 204 injections). Prefilled syringes were associated with a trend toward decreased risk of suspected endophthalmitis (odds ratio 0.59; 95% confidence interval 0.31-1.12; P = .10) and a statistically significant decreased risk of culture-positive endophthalmitis (odds ratio 0.19; 95% confidence interval 0.045-0.82; P = .025). Average logMAR vision loss at final follow-up was significantly worse for eyes that developed endophthalmitis from the conventional ranibizumab preparation compared to the prefilled syringe group (4.45 lines lost from baseline acuity vs 0.38 lines lost; P = .0062). Oral-associated flora was found in 27.3% (6/22) of conventional ranibizumab culture-positive endophthalmitis cases (3 cases of Streptococcus viridans, 3 cases of Enterococcus faecalis) compared to 0 cases in the prefilled ranibizumab group.

CONCLUSION

In a large, multicenter, retrospective study the use of prefilled syringes during intravitreal injection of ranibizumab was associated with a reduced rate of culture-positive endophthalmitis, including from oral flora, as well as with improved visual acuity outcomes.

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.

Vancomycin-Associated Hemorrhagic Occlusive Retinal Vasculitis: A Clinical-Pathophysiological Analysis

PURPOSE

To derive novel insights into the pathophysiology of vancomycin-related hemorrhagic occlusive retinal vasculopathy (HORV) through a careful clinicopathologic correlation.

METHODS

We retrospectively reviewed the clinical and pathologic course of 2 consecutive patients who developed HORV. The clinical history, multimodal imaging, ultrasound biomicroscopy (UBM), and intraoperative and histologic findings are reported.

RESULTS

Both patients presented with decreased vision and eye pain within 1 week following otherwise uncomplicated cataract extraction and were diagnosed with HORV after endophthalmitis was ruled out. Both patients presented with significant ocular discomfort that progressively worsened, and both experienced a dismal visual outcome despite early aggressive medical and surgical therapy. One patient requested enucleation for a blind and painful eye. Upon histologic examination of this eye, the iris and ciliary body appeared to be infarcted with separation of the iris and ciliary epithelia from their adjacent stromal components. These findings were corroborated by UBM of the second patient. Histologic examination of the posterior segment demonstrated severe hemorrhagic necrosis of the neurosensory retina and an occlusive nonarteritic vasculopathy of the retina and choroid. The choroid was thickened by prominent nongranulomatous chronic inflammation accompanied by a glomeruloid proliferation of small vessels. The inflammatory infiltrate was almost exclusively confined to the choroid and consisted of predominantly T cells. There was conspicuous absence of inflammatory cells in the retina and no histologic evidence of leukocytoclastic vasculitis.

CONCLUSIONS

HORV is a rare condition that can lead to profound vision loss. Significant ocular pain can be a presenting sign of HORV in cases with severe iris and ciliary body ischemia. Although it has been suggested that HORV is a form of leukocytoclastic retinal vasculitis, the histologic findings herein indicate that the pathophysiology is more complex. It is grounded in a necrotizing retinal vasculopathy in the absence of retinal vasculitis, chronic nongranulomatous choroiditis, and an unusual glomeruloid proliferation of endothelial cells in the choroid and elsewhere in the eye.

RETINAL VASCULAR TORTUOSITY AND EXUDATIVE RETINOPATHY IN A FAMILY WITH DYSKERATOSIS CONGENITA MASQUERADING AS FAMILIAL EXUDATIVE VITREORETINOPATHY

PURPOSE

To report a novel presentation of dyskeratosis congenita masquerading as familial exudative vitreoretinopathy.

METHODS

Observational case series involving single family and literature review.

RESULTS

A brother and sister were diagnosed with familial exudative vitreoretinopathy at ages 4 and 2, respectively. Both patients were managed with laser photocoagulation. Eight years after the initial presentation, both siblings developed pancytopenia secondary to bone marrow failure. Laboratory work-up revealed severely shortened telomere length in both patients, and genetic testing revealed a missense mutation in the gene that encodes the reverse transcriptase component of telomerase, confirming the diagnosis of dyskeratosis congenita. The father of both children was a carrier of the same mutation, who exhibited marked retinal vascular tortuosity of the second-order vessels.

CONCLUSION

Dyskeratosis congenita is a severe multisystem disorder, which should be considered in cases of pediatric exudative retinopathies with concurrent signs and/or symptoms of bone marrow failure.

Impact of Microscope-Integrated OCT on Ophthalmology Resident Performance of Anterior Segment Surgical Maneuvers in Model Eyes

Purpose

The integration of swept-source optical coherence tomography (SS-OCT) into the operating microscope enables real-time, tissue-level three-dimensional (3D) imaging to aid in ophthalmic microsurgery. In this prospective randomized controlled study, we evaluated the impact of SS microscope-integrated OCT (MI-OCT) on ophthalmology residents' performance of ophthalmic microsurgical maneuvers.

Methods

Fourteen ophthalmology residents from a single institution were stratified by year of training and randomized to perform four anterior segment surgical maneuvers on porcine eyes with (MI-OCT+) or without (MI-OCT−) direct intraoperative OCT guidance. Subsequently, both groups repeated the same maneuvers without MI-OCT feedback to test whether initial MI-OCT experience affected subsequent surgical performance. Finally, the MI-OCT− group was crossed over and allowed to repeat the same maneuvers with direct MI-OCT guidance. Each resident completed a survey at the completion of the study.

Results

With direct MI-OCT feedback, residents demonstrated enhanced performance in depth-based anterior segment maneuvers (corneal suture passes at 50% and 90% depth and corneal laceration repair) compared with the residents operating without MI-OCT. Microscope-integrated OCT+ residents continued to outperform the controls when both groups subsequently operated without MI-OCT. For clear corneal wound geometry, there was no statistically significant effect of MI-OCT as applied in this study. Overall, the resident surgeons rated their subjective experience of using MI-OCT very favorably.

Conclusions

Microscope-integrated OCT feedback enhances performance of ophthalmology residents in select anterior segment surgical maneuvers. Microscope-integrated OCT represents a valuable tool in the surgical education of ophthalmology residents.

SUCCESSFUL REPAIR OF RECURRENT OPTIC DISK PIT MACULOPATHY WITH AUTOLOGOUS PLATELET RICH PLASMA: REPORT OF A SURGICAL TECHNIQUE

PURPOSE

To describe vitreoretinal surgical technique of using autologous platelet-rich plasma to aid in surgical repair of optic pit maculopathy refractive to previous vitrectomy.

METHODS

A case of an 18-year-old woman presenting with serous macular detachment secondary to optic pit is reported. Patient had previously undergone vitrectomy and peripapillary laser, but had recurrence of subretinal fluid and worsening visual acuity. Autologous platelet-rich plasma was harvested from the patient's blood and purified using Arthrex ACP kit (Arthrex, Inc, Naples, FL). Repeat pars plana vitrectomy was performed with internal limiting membrane peeling extending to the optic nerve. Platelet-rich plasma was layered over the pit and long-acting gas tamponade performed with face-down positioning.

RESULTS

At 8 months of follow-up, subretinal fluid was resolved, the connection between optic pit and subretinal space collapsed and the ellipsoid zone near completely reconstituted on optical coherence tomography. The patient's vision improved significantly from 20/100 to 20/50, which is largely limited by posterior subcapsular cataract.

CONCLUSION

Platelet-rich plasma can augment anatomical and visual outcomes in surgical repair of optic pit maculopathy.

Ocular Pharmacology for Scleritis: Review of Treatment and a Practical Perspective

Scleritis is defined as an infectious or noninfectious inflammation of the sclera that can be broadly categorized according to anatomic location (ie, anterior or posterior) and whether the process is necrotizing or non-necrotizing. Treatment for scleritis is dictated by the etiology of the inflammation, with infectious forms requiring treatment of the inciting agent and noninfectious forms requiring treatment of the underlying inflammation with immunosuppression. Pharmacotherapy for noninfectious scleritis can be classified according to delivery route (eg, local or systemic) and mechanism of action (eg, biologic or nonbiologic). This review will briefly summarize the classification scheme for scleritis before reviewing in depth both systemic and local pharmacotherapies that can be used to effectively treat an eye afflicted by either infectious or noninfectious scleritis. Traditional anti-inflammatory agents such as nonsteroidal anti-inflammatory drugs, steroids, and immunomodulatory therapy will be discussed, as well as newer biologic therapies such as antitumor necrosis factor alpha and anti-CD20 agents.

Scleral-Fixated Intraocular Lenses: Past and Present

Intraocular lenses (IOLs) can have inadequate support for placement in the capsular bag as a result of ocular trauma, metabolic or inherited conditions such as Marfan's syndrome or pseudoexfoliation, or complicated cataract surgery. Surgical options for patients with inadequate capsular support include alternative placement in the anterior chamber (ACIOLs), fixation to the iris, or fixation to the sclera. The surgical techniques for each of these approaches have improved considerably over the last several decades resulting in improved visual and ocular outcomes. If no capsular or iris support exists, the surgeon can fixate an IOL to the sclera or the patient can remain aphakic. IOLs can be fixated to the sclera using sutures or by tunneling the IOL haptics into the sclera without sutures. This review summarizes the pre-operative considerations, surgical techniques, outcomes, and unique complications associated with implantation of scleral-fixated IOLs.

Prediction of Anti-VEGF Response in Diabetic Macular Edema After 1 Injection

Purpose

With multiple anti-vascular endothelial growth factor and steroid therapies available for diabetic macular edema (DME), there is a need for early determination of the best treatment for a particular patient to prevent irreversible vision loss from chronic DME. In this study, we classify patients as responders or non-responders to anti-vascular endothelial growth factor (VEGF) monotherapy in the treatment of DME after a single anti-VEGF injection.

Methods

The study was designed as a single center, retrospective, interventional case series. We included patients who received 3 consecutive monthly injections with the same anti-VEGF agent. We excluded patients who were treated for DME in the preceding 3 months with any form of anti-VEGF therapy. Visual acuity and central retinal thickness (CRT) data were followed for one year. Receiver operating characteristic (ROC) curve analysis was performed in order to identify cutoff values for identifying responders.

Results

107 eyes were reviewed, with 40 eyes of 34 patients meeting all inclusion criteria. Based on ROC curve analysis, a reduction in CRT by > 15% at 1-month, identified eyes that responded to treatment and had a >25% reduction in CRT at 3-months (sensitivity 0.75, specificity 0.92).

Conclusion

DME eyes that have early response to anti-VEGF treatment by reduction in CRT will have significant response to treatment by 3 months.

Simultaneous dexamethasone intravitreal implant and anti-VEGF therapy for neovascular age-related macular degeneration resistant to anti-VEGF monotherapy

PURPOSE

To evaluate the efficacy of a dexamethasone intravitreal implant in combination with intravitreal anti-VEGF agents for treatment resistant neovascular age-related macular degeneration (nvAMD).

METHODS

This study was designed as a single-center, retrospective interventional case series. Consecutive patients with treatment-resistant nvAMD underwent simultaneous combined injection of anti-VEGF agent and dexamethasone intravitreal implant. Eighteen patients with mean age of 81.5 years were included. Patients received average of 26.3 anti-VEGF injections before dual therapy, with mean follow up of 8.2 months after dual therapy.

RESULTS

Dual therapy produced a significant mean decrease in CFT (126.3 μm), compared to a mean increase of 29.9 μm when treated with anti-VEGF monotherapy (p=0.0017). Patients also had mean decrease in MCV of -0.85 mm³ with dual therapy compared with anti-VEGF monotherapy (p=0.0014). There was a moderate correlation between the number of prior anti-VEGF injections and the magnitude of anatomic response, suggesting that shorter disease duration may positively influence response to combined treatment. Although there was a slight trend towards improved mean visual acuity after dual therapy, these differences did not reach statistical significance. Nevertheless, with combination treatment, 33% of patients gained one or more lines of vision. Dual therapy resulted in a significantly lower number of required anti-VEGF injections (4.25 vs 5.33) and an increase of the anti-VEGF injection-free interval to 1.41 months from 1.12 months during the 6 months following dual therapy compared to the same interval before dual therapy. Dual therapy was well tolerated; two eyes developed mild IOP elevation effectively managed with topical therapy and one patient developed worsening cataract.

CONCLUSIONS

Combined treatment of anti-VEGF with the dexamethasone intravitreal implant is a viable alternative for treatment-resistant nvAMD, and may reduce treatment burden. Earlier treatment with dual therapy may be beneficial to maximize anatomic and visual outcomes in these patients.

Sutureless Intrascleral Fixation of Secondary Intraocular Lens Using 27-Gauge Vitrectomy System

Transconjunctival sutureless intrascleral fixation is an important surgical option for secondary intraocular lens (IOL) implantation. In this report, the authors describe the technique of using a 27-gauge platform to perform pars plana vitrectomy, lensectomy, and sutureless scleral IOL fixation in a patient with crystalline lens dislocation secondary to Marfan's syndrome. Case report and detailed description of the surgical technique are discussed.

Hybrid 25- and 27-Gauge Vitrectomy for Complex Vitreoretinal Surgery

BACKGROUND AND OBJECTIVE

The authors report the technique of using the 27-gauge (G) vitreous cutter through 25-G valved cannulas to allow hybrid instrumentation of both gauges.

PATIENTS AND METHODS

Vitrectomy is initiated with standard placement of 25-G valved cannulas, followed by insertion of a 27-G vitreous cutter through the 25-G cannulas.

RESULTS

The hybrid procedure emphasizes the advantages of both platforms: The 25-G cutter is more efficient for core vitrectomy and is more rigid to facilitate peripheral vitrectomy; the 25-G platform enjoys a wider armamentarium of instrumentation options; and the smaller profile of the 27-G cutter can be maneuvered more easily into tight surgical planes to act analogous to vertical scissors, with the added benefits of aspiration and spatula-like features. The authors illustrate this technique in three cases: diabetic tractional retinal detachment with dense plaques, posterior stage 4B retinopathy of prematurity, and sutureless scleral fixation of an intraocular lens.

CONCLUSIONS

Hybrid use of the 25-G and 27-G platforms offers greater versatility for the management of complex vitreoretinal conditions.

Screening and treatments using telemedicine in retinopathy of prematurity

Several studies have validated the role of telemedicine as a new powerful screening and diagnostic tool for retinal disorders, such as diabetic retinopathy and retinopathy of prematurity. With regard to retinopathy of prematurity, bedside examination with binocular indirect ophthalmoscopy has been the gold standard technique for screening, yet with several limitations. Herein, we review the current evidence that supports the role of telemedicine for the screening of infants with retinopathy of prematurity.

Profound vascular stasis of retina and optic nerve following retrobulbar anesthesia

INTRODUCTION

We aim to describe a mechanism of vision loss following vitrectomy surgery with retrobulbar block (RBB) associated with severe vascular stasis of the optic nerve and macula in order to improve safety of local anesthesia for ophthalmic surgery.

CASE PRESENTATION

We report three cases of patients who underwent pars plana vitrectomy (PPV) with retrobulbar anesthesia with no retrobulbar hemorrhage or elevated intraocular pressure (IOP). At the beginning, in each case, hypoperfusion of optic nerve and macula was noted. In the case of one patient with significant vasculopathic risk factors, the vascular stasis was severe, while in the other two cases, it was mild-to-moderate. In all cases, the perfusion of posterior pole began to improve almost immediately following the start of PPV. Because the IOP was not elevated and no retrobulbar hemorrhage was present, this suggested a compartment syndrome in the intraconal space. The patient with severe vascular stasis developed finger-counting vision but had normal postoperative angiogram findings and unrevealing cardiovascular workup. In the other two milder cases, the occurrence of ischemia was not visually significant.

CONCLUSION

Intraoperative ischemia should be considered in all cases of unexplained vision loss after ophthalmic surgery using RBB. Attention to vasculopathic risk factors and intra-operative hemodynamic parameters, in addition to the use of parabulbar block, may avoid this complication and permanent vision loss.

Semaphorin4A Is Cytotoxic to Oligodendrocytes and Is Elevated in Microglia and Multiple Sclerosis

We have previously established that T cell immunoglobulin and mucin domain containing 2 (Tim2) is an H-ferritin receptor on oligodendrocytes (OLs). Tim2 also binds Semaphorin4A (Sema4A). Sema4A is expressed by lymphocytes, and its role in immune activation is known; however, its relationship to diseases that are known to have myelin damage has not been studied. In this study, we demonstrate that Sema4A is cytotoxic to OLs in culture: an effect accompanied by process collapse, membrane blebbing, and phosphatidylserine inversion. We further demonstrate that Sema4A preferentially binds to primary OLs but not astrocytes: an observation consistent with the lack of expression of Tim2 on astrocytes. We found that Sema4A protein levels are increased within multiple sclerosis plaques compared with normal-appearing white matter and that Sema4A induces lactate dehydrogenase release in a human OL cell line. The chief cellular source of Sema4A within the multiple sclerosis plaques appears to be infiltrating lymphocytes and microglia. Macrophages are known to express Sema4A, so we interrogated microglia as a potential source of Sema4A in the brain. We found that rat primary microglia express Sema4A which increased after lipopolysaccharide activation. Because activated microglia accumulate iron, we determined whether iron status influenced Sema4A and found that iron chelation decreased Sema4A and iron loading increased Sema4A in activated microglia. Overall, our data implicate Sema4A in the destruction of OLs and reveal that its expression is sensitive to iron levels.

Neovascular events in eyes with central retinal vein occlusion undergoing serial bevacizumab or ranibizumab intravitreal injections: a retrospective review

PURPOSE

To characterize the onset and type of neovascular events in eyes with central retinal vein occlusion (CRVO) undergoing serial anti-VEGF therapy.

METHODS

Consecutive eyes undergoing serial intravitreal bevacizumab or ranibizumab injections for treatment of CME secondary to CRVO were identified. Pertinent data was retrospectively collected and included type and onset of the neovascular event, and the treatment free interval from last injection until the neovascular event. Kaplan-Meier life table analysis was performed to determine the differential effects of baseline perfusion status, early initiation of anti-VEGF treatment (within 3 months of CRVO onset) versus later treatment, and continuous (1-month±2 weeks) versus discontinuous treatment interval (>1.5 months) on time until neovascular event.

RESULTS

Of 31 eligible eyes, 12 (39%) and 19 (61%) presented with perfused and ischemic CRVO, respectively. The mean duration from CRVO until the onset of any neovascular event was 17.0±10.3 months. The mean treatment-free interval prior to any neovascular event was 6.2±7.3 months. On average, 5.3±3.2 anti-VEGF injections were given prior to any neovascular event. Neovascularization of the iris or angle occurred in 18 eyes (58%), vitreous hemorrhage associated with neovascularization was observed in 9 eyes (29%) and neovascularization of the disc developed in 5 eyes (16%). Neovascular events showed a trend towards occurring later in eyes with perfused CRVO at baseline (log rank test, P=0.07).

CONCLUSION

Neovascular events occur in eyes with CRVO undergoing serial anti-VEGF therapy, and these events may be delayed compared to the natural history of CRVO-associated neovascularization. Iris neovascularization occurred most frequently.

Choroid plexus in the eye: a case study

PURPOSE

The purpose of this report is to describe a pediatric case of total retinal detachment (RD) with secondary glaucoma in the setting of posterior coloboma with the metaplastic retinal pigment epithelium showing abrupt transition to choroid plexus tissue.

METHODS

Retrospective case report.

RESULTS

A 3-month-old patient presented with leukocoria and enlarged right eye. She was found to have a funnel RD with anterior displacement of lens-iris diaphragm and secondary glaucoma. Orbital imaging ruled out retinoblastoma, and posterior coloboma was identified. Intraocular pressures remained significantly elevated despite maximal medical therapy on glaucoma drops and transscleral cycloablation, and the eye was enucleated for comfort. Histologic analysis confirmed neovascularization of the iris, total RD, and posterior coloboma with the associated metaplastic retinal pigment epithelium showing abrupt transition to choroid plexus tissue.

CONCLUSION

This is the first reported case of choroid plexus in the human eye. A close association of choroid plexus with coloboma and RD raises possibility that this tissue may have functionally contributed to pathogenesis of RD by secreting cerebrospinal fluid within subretinal space.

Current and investigational pharmacotherapeutic approaches for modulating retinal angiogenesis

Retinal vascular development is a carefully orchestrated developmental process during which retinal and choroidal vasculature form to provide a dual vascular supply to the neurosensory retina and retinal pigment epithelium. The most common causes of vision loss in children and adults involve at least in part perturbation of the normal vascular physiology or development. Vascular endothelial growth factor has emerged as a key molecular regulator of retinal vascular development as well as retinal and choroidal neovascularization, which underlie the pathophysiology of many retinal diseases. Over the past decade, the advent of injectable pharmacotherapeutic agents into the vitreous cavity of the eye has revolutionized our management of neovascular age-related macular degeneration and other retinal diseases and has, for the first time, offered an opportunity to improve vision rather than just slow the progression of disease processes. The transient duration of these agents, however, requires chronic treatment with repeated intraocular injections and significant treatment burden for patients and the healthcare system. Novel treatments modulating retinal angiogenesis offer the promise of improved efficacy, decreased treatment burden and improved cost-effectiveness.

The mechanism of vanadium-mediated developmental hypomyelination is related to destruction of oligodendrocyte progenitors through a relationship with ferritin and iron

The second post-natal week in rat is the period of the most intense oligodendrocyte development and myelination. This period coincides with peak iron import by oligodendrocytes. During that time oligodendrocyte progenitors (OPCs) are sensitive to agents that may disturb normal iron homeostasis and assimilation of iron into these cells. One mechanism by which iron homeostasis can be disrupted is by environmental exposure to other metals. Vanadium is a transition metal, and exposure to vanadium during early brain development produces hypomyelination with variety of related neuro-behavioral phenotypes. In the current study, we investigated mechanisms of hypomyelination induced by vanadium exposure in developing rat brain. We demonstrate that both in vivo and in vitro, OPCs are more sensitive to vanadium exposure than astrocytes or mature oligodendrocytes. Vanadium exposure in OPCs resulted in increased ROS generation and increased annexinV labeling suggestive of apoptosis. Because ferritin is a major iron delivery protein for oligodendrocytes, we exposed the cells to recombinant ferritin and iron both of which exacerbated vanadium cytotoxicity, while the iron chelator desferroxamine (DFO) prevented cytotoxic/apoptotic effects of vanadium. To illustrate relationship between ferritin and vanadium, we demonstrate that vanadium exacerbated DNA nicking produced by iron-rich spleen ferritin, but not iron-poor apoferritin, resulting in a single and double strand breaks in a DNA relaxation assay. We propose that developmental exposure to vanadium interferes with normal iron assimilation into oligodendrocytes resulting in oxidative stress and apoptosis. Therefore, depletion of OPCs due to vanadium exposure in early post-natal period may be an important mechanism of vanadium-induced hypomyelination.

Tim-2 is the receptor for H-ferritin on oligodendrocytes

Oligodendrocytes stain more strongly for iron than any other cell in the CNS, and they require iron for the production of myelin. For most cell types transferrin is the major iron delivery protein, yet neither transferrin receptor protein nor mRNA are detectable in mature oligodendrocytes. Thus an alternative iron delivery mechanism must exist. Given the significant long term consequences of developmental iron deficiency and the iron requirements for normal myelination, identification of the iron delivery mechanism for oligodendrocytes is important. Previously we have reported that oligodendrocytes bind H-ferritin and that H-ferritin binds to white matter tracts in vivo. Recently, T cell immunoglobulin and mucin domain-containing protein-2 (Tim-2) was shown to bind and internalize H-ferritin. In the present study we show that Tim-2 is expressed on oligodendrocytes both in vivo and in vitro. Further, the onset of saturable H-ferritin binding in CG4 oligodendrocyte cell line is accompanied by Tim-2 expression. Application of a blocking antibody to the extracellular domain of Tim-2 significantly reduces H-ferritin binding to the differentiated CG4 cells and primary oligodendrocytes. Tim-2 expression on CG4 cells is responsive to iron; decreasing with iron loading and increasing with iron chelation. Taken together, these data provide compelling evidence that Tim-2 is the H-ferritin receptor on oligodendrocytes suggesting it is the primary mechanism for iron acquisition by these cells.

Cytokine toxicity to oligodendrocyte precursors is mediated by iron

Inflammatory processes play a key role in the pathogenesis of a number of common neurodegenerative disorders such as Alzheimer's disease (AD), Parkinson's disease (PD), and multiple sclerosis (MS). Abnormal iron accumulation is frequently noted in these diseases and compelling evidence exists that iron is involved in inflammatory reactions. Histochemical stains for iron repeatedly demonstrate that oligodendrocytes, under normal conditions, stain more prominently than any other cell type in the brain. Therefore, we examined the hypothesis that cytokine toxicity to oligodendrocytes is iron mediated. Oligodendrocytes in culture were exposed to interferon-gamma (IFN-gamma), interleukin-1beta (IL-1beta), and tumor necrosis factor-alpha (TNF-alpha). Toxicity was observed in a dose-dependent manner for IFN-gamma and TNF-alpha. IL-1beta was not toxic in the concentrations used in this study. The toxic concentration of IFN-gamma, and TNF-alpha was lower if the cells were iron loaded, but iron loading had no effect on the toxicity of IL-1beta. These data provide insight into the controversy regarding the toxicity of cytokines to oligodendrocytes by revealing that iron status of these cells will significantly impact the outcome of cytokine treatment. The exposure of oligodendrocytes to cytokines plus iron decreased mitochondrial membrane potential but activation of caspase 3 is limited. The antioxidant, TPPB, which targets mitochondria, protected the oligodendrocytes from the iron-mediated cytotoxicity, providing further support that mitochondrial dysfunction may underlie the iron-mediated cytokine toxicity. Therapeutic strategies involving anti-inflammatory agents have met with limited success in the treatment of demyelinating disorders. A better understanding of these agents and the contribution of cellular iron status to cytokine toxicity may help develop a more consistent intervention strategy.