Multimodal Imaging of an Idiopathic Vascularized Epiretinal Membrane: A Case Report

BACKGROUND Idiopathic epiretinal membranes (ERMs) are commonly associated with fibrovascular tissue, primarily observed in ischemic retinopathies. However, idiopathic vascularized ERMs (IVEM) are exceedingly rare, and their pathogenesis and clinical course remain poorly understood. This report aims to contribute to the limited literature on IVEM, shedding light on its characteristics and potential implications for patient management. CASE REPORT We present the case of a 70-year-old man diagnosed with idiopathic ERM in the left eye, revealing a neovascular complex within the membrane. Despite the absence of ocular symptoms and medical history, multimodal imaging using the Nidek Mirante, including spectral domain optical coherence tomography (SD-OCT) and optical coherence tomography angiography (OCT-A), revealed a thick pre-retinal hyper-reflective line with a partial posterior vitreous detachment and an abnormal vascular complex resembling a pruned-vascular-tree pattern. Notably, fluorescein angiography confirmed hyperfluorescence and leakage corresponding to the observed vessels. Despite the rarity of IVEM, the patient remained asymptomatic, and observation was deemed appropriate. CONCLUSIONS IVEM poses a rare challenge in clinical practice, necessitating a comprehensive understanding of its features and potential complications. While the etiopathogenesis remains unclear, hypertension has been proposed as a contributing factor. This case adds valuable insights to the growing literature on IVEM, emphasizing the importance of multimodal imaging in diagnosis and decision-making. Given the limited reports and varied treatment outcomes, managing IVEM requires careful consideration of observation and various therapeutic approaches, highlighting the need for further research to optimize patient care.

Early-Phase Perceptions of COVID-19's Impact on Ophthalmology Practice Patterns: A Survey from the Pan-American Association of Ophthalmology

Purpose

The COVID-19 pandemic affected medical practice worldwide due to interventions to prevent spreading. Its effect on ophthalmology practices in Latin America has not yet been explored. We aimed to assess the perceptions about the pandemic from countries' ophthalmological national and subspecialty retina societies affiliated to the Pan-American Association of Ophthalmology (PAAO).

Patients and Methods

A survey-based study of leaders of national ophthalmological and retinal societies was conducted. The survey was sent by email to 30 societies, from which 20 responded (12 countries, 66.6% response rate). It included closed- and open-ended questions about (1) operational capacity and precautions, (2) telemedicine and virtual care, (3) procedures, and (4) post-pandemic considerations.

Results

There was a marked decline in ophthalmology patient visits (80-95%) and elective surgeries (90%) during 2020 compared to before the pandemic. Precautions like temperature checks, mask usage, and social distancing were widely implemented while personal protective equipment (PPE) availability varied. Telemedicine use was limited due to lack of experience with it. Reopening plans focused on maintaining precautions and gradually resuming activities. Economic and security concerns were raised, and adherence to guidelines was emphasized. Respondents acknowledged the need to adapt to a "new normal". Long duration drugs, fewer imaging studies, and shorter wait times were preferred; however, availability of long duration drugs was limited.

Conclusion

The pandemic impacted ophthalmology in Latin America, with reduced patient visits, procedures, and surgeries. Delayed treatment and complications were likely the result of the pandemic.

Intravitreal quantum dots for retinitis pigmentosa: a first-in-human safety study

Background: Studies indicate that electrical stimulation of retinitis pigmentosa (RP) retina is beneficial. Quantum dots (QDs) can convert light to electrical stimulus and therefore may have therapeutic potential for RP. Methods: This was an open-label, fellow eye-controlled, first-in-human safety study. Five adults with end-stage (arm A) and 15 with severe (arm B) RP received one or two intravitreal injections of 0.2 or 2μM cadmium/selenium 655 Alt QDs. Results: No adverse events were attributed to QDs. In arm A, median best corrected visual acuity was unchanged. In arm B, mean best corrected visual acuity improved from 6/398 to 6/177, versus 6/147 to 6/144 in the fellow eye. Conclusion: Intravitreal QDs can be safely administered to patients with RP. Vision appears to benefit and further validating studies are justified.

Survey of Intravitreal Injection Techniques Among Retina Specialists in Mexico

Purpose

To report technique preferences for intravitreal injections among retina specialists in Mexico.

Methods

Cross-sectional survey. Ophthalmologists with a two-year retina training, active members of the Mexican Retina Association, were contacted through email to answer a survey consisting of 37 items regarding their IVI application technique.

Results

A total of 133 retina specialists participated, with a response rate of 78%. Forty-five percent applied the intravitreal injections in an operating room designated for the procedure. Sixty-three percent reported never injecting both eyes on the same day. Ninety-six percent wore a face mask during the procedure and 91% wore gloves. Eighty-two percent used a lid speculum. Tetracaine drops were the anesthetic method employed by 97% of participants. All participants utilized povidone-iodine for antisepsis. Eighty percent measured the puncture site with a caliper. Superotemporal quadrant was the one chosen to place the injection by 63% of participants. Fifty-nine percent indicated post-injection antibiotic drops for several days. Post-injection counting fingers visual acuity was verified by 53% of the participants. Fifty-six percent of the participants placed an eye-patch after the procedure.

Conclusion

There are different practices regarding the application of intravitreal injections among retina specialists in Mexico. Performing this type of survey periodically could show changes in preferences, as new evidence is incorporated into clinical practice.

Cilioretinal Artery Branch Avulsion Secondary to Surgical Embolectomy: Management and Outcome

We report the trans-operative approach and short-term outcome of a patient who suffered a traumatic avulsion of the cilioretinal artery branch during the surgical management of a cilioretinal arterial branch occlusion (CRABO) with intraocular embolectomy. A patient with acute CRABO underwent a pars plana vitrectomy with in situ embolectomy. The blocked artery was incised using 25 gauge vertical scissors, and embolus manipulation was done using microsurgical forceps. During embolus extraction, the occluded cilioretinal artery and its branch were inadvertently avulsed and torn with subsequent intense bleeding. Laser and endodiathermy were used for acute hemostasis. The maneuvers created an unintended retinochoroidal anastomosis. Visual field improvement was noted 3 months after the surgery. In the event of a complicated surgical embolectomy with the avulsion of the artery, the formation of a retinochoroidal anastomosis and reperfusion of the occluded may occur along with the improvement of visual fields in some cases.

Cilioretinal artery branch avulsion secondary to surgical embolectomy: management and outcome. Case report

We report the trans-operative approach and short-term outcome for a patient who suffered a traumatic avulsion of the cilioretinal artery branch during the surgical management of a cilioretinal arterial branch occlusion with intraocular embolectomy. The patient underwent a pars plana vitrectomy with in situ embolectomy. The blocked artery was incised using 25 Ga vertical scissors, and embolus manipulation was performed using microsurgical forceps. During embolus extraction, the occluded cilioretinal artery and its branch were inadvertently avulsed and torn with subsequent intense bleeding. Laser and endodiathermy were used for acute hemostasis. The maneuvers created an unintended retinochoroidal anastomosis. Visual-field improvement was noted three months after the surgery. In the event of a complicated surgical embolectomy with the avulsion of the artery, the formation of a retinochoroidal anastomosis and reperfusion of the occluded artery may occur along with the improvement of the visual field in some cases.

Evaluation of VEGF gene polymorphisms and proliferative diabetic retinopathy in Mexican population

AIM

To assess if the included vascular endothelial growth factor (VEGF) polymorphisms rs3025035, rs3025021 and rs2010963 are associated to proliferative retinopathy in a Mexican population with type 2 diabetes mellitus (T2DM).

METHODS

A case-control study was conducted in adult individuals with T2DM associated to proliferative retinopathy or non-proliferative retinopathy from Oct. 2014 to Jun. 2015 from the Retina Department of the Asociation to Prevent Blindness in Mexico. The selected patients were adults with a diagnosis of T2DM ≥5y. All subjects had a comprehensive ocular examination and the classification of the retinopathy severity was made considering the Early Treatment Diabetic Retinopathy Study (ETDRS) standardization protocols. Genomic DNA was extracted from whole fresh blood. All samples were genotyped by qPCR for selected VEGF polymorphisms. Hardy-Weinberg equilibrium was calculated by comparing Chi-square values between the expected and the observed values for genotype counts.

RESULTS

In total 142 individuals were enrolled, 71 individuals with T2DM and associated proliferative retinopathy and 71 individuals with non-proliferative retinopathy. One-sided Fisher's exact test was performed for rs3025021 [OR (95% CI)=0.44(0.08-2.2); P=0.25] and rs2010963 [OR (95% CI)=0.63(0.25-1.6); P=0.23]. The minor allelic frequencies obtained were 26% for rs3025021, 10% for rs3025035 and 61% for rs2010963. The pairwise linkage disequilibrium between the three SNP was assessed, and was as follows: rs3025021 vs rs3025035: D'=1.0, r²=0.1043, P≤0.0001; rs3025021 vs rs2010963: D'=0.442, r²=0.0446, P=0.149; rs3025035 vs rs2010963: D'=0.505, r²=0.0214, P=0.142.

CONCLUSION

This is the first analysis involving VEGF polymorphisms and proliferative diabetic retinopathy in a Mexican population. A major finding of the present study is that none of the polymorphisms studied was significantly associated with proliferative retinopathy. Based on these results, we can infer that different populations have different associations for the same polymorphisms.

Growth of Scytalidium sp. in a counterfeit bevacizumab bottle

After drawing a dose from an closed bevacizumab (Avastin) bottle, a fungus-like foreign body was observed inside. Samples from the vial were cultured in Sabouraud Emmons media. Growth of multiple light brown colonies with dark pigment was observed after 10 days. The species was identified as Scytalidium sp.Vial, analysis reported that the seal was lacking proper identification measures and that the label, batch number and expiry date did not correspond to a genuine product. Chemical analysis showed no protein, but 3% of polyethylene glycol, citrate and ethanol. Counterfeit bevacizumab is a real situation that poses a significant risk for ophthalmology and oncology patients. The medical community should be aware of this situation in order to enforce adequate preventive measures.

Retinal fluorescein angiographic changes following intravitreal anti-VEGF therapy

PURPOSE

To describe the retinal vascular morphology in eyes injected with intravitreal bevacizumab for treatment-requiring retinopathy of prematurity (ROP).

METHODS

In this prospective, nonrandomized case series, fundus photographs and fluorescein angiography in patients diagnosed with stage 3 threshold or prethreshold ROP, were obtained immediately before and 1 month after injection of 0.03 cc (0.75 mg) of intravitreal bevacizumab using wide-field digital pediatric imaging system.

RESULTS

A total of 47 eyes of 26 patients were included. Before treatment, fluorescein angiography showed vascular abnormalities, including capillary nonperfusion throughout and shunting in the vascularized retina, demarcation line, limited vessel development, new vessels leakage, avascular periphery and absence of foveal avascular zone. After intravitreal bevacizumab, fluorescein angiography showed involution of the neovascularization, flattening of the demarcation line and subsequent growth of vessels to the capillary-free zones. During the following weeks large areas devoid of microvessels were seen as well as vascular remodeling with uneven spacing of the retinal capillaries and vascular loops in the areas that were previously devoid of vessels. In some patients, retinal vessels in the far periphery never developed: patients with these findings did not subsequently develop pathological neovascularization.

CONCLUSIONS

In this study cohort, patients showed improvement of their abnormal vascular findings after intravitreal bevacizumab, however even when the vascular pattern remained abnormal, there was creation of small vessels, establishment of directional flow, maturation of retinal vessels, and adjustment of vascular density.

Perfluorocarbon-perfused 23 gauge three-dimensional vitrectomy for complicated diabetic tractional retinal detachment

Background

Perfluorocarbon liquid (PCL)-perfused vitrectomy has been shown in previous studies to be feasible, safe, and to have advantages in managing complicated cases of tractional retinal detachment. The present study had the objectives of describing the anatomical results and measuring surgical time and PCL consumption when combining PCL-perfused techniques with modern vitrectomy equipment.

Methods

A prospective, interventional consecutive case series was investigated. We enrolled patients with diabetic tractional retinal detachment, complicated by proliferative vitreoretinopathy and poor vision. A 23 gauge PCL-perfused vitrectomy was done with three-dimensional settings. During the procedure, we assessed the degree of surgical bleeding, visualization quality, and difficulty of membrane dissections. Visual acuity, intraocular pressure, and anatomical success were assessed at one and 3 months of follow-up.

Results

Twelve patients were enrolled in this study. There were no statistical significant changes in intraocular pressure and visual acuity throughout the follow-up period. Surgery was performed in a hemorrhage-free environment in almost all cases, with good visualization and low technical difficulty. The mean complete surgical time was 94.92 ± 25.03 minutes. The mean effective vitrectomy time was 22.50 ± 19.04 minutes and the mean PCL consumption was 25.08 ± 9.76 mL, with a speed of 1.11 mL/minute. Anatomical success was 67% at 3 months.

Conclusion

Although the technique proved to have some advantages in managing complicated cases of diabetic tractional retinal detachment, there was a high consumption of PCL. A redesign of the entire system is needed in order to decrease the amount of PCL needed for the technique.

Intraocular and systemic levels of vascular endothelial growth factor in advanced cases of retinopathy of prematurity

PURPOSE

To measure vitreous, aqueous, subretinal fluid and plasma levels of vascular endothelial growth factor in late stages of retinopathy of prematurity.

METHODS

Interventional study. We enrolled patients with clinical diagnoses of bilateral stage V retinopathy of prematurity, confirmed by b-scan ultrasound and programmed for vitrectomy. During surgery we took samples from blood, aqueous, vitreous, and subretinal fluids. The vascular endothelial growth factor concentration in each sample was measured by ELISA reaction. A control sample of aqueous, vitreous and blood was taken from patients with congenital cataract programmed for phacoemulsification. For statistical analysis, a Mann-Whitney and a Wilcoxon W test was done with a significant P value of 0.05.

RESULTS

We took samples of 16 consecutive patients who met the inclusion criteria. The vascular endothelial growth factor levels in the study group were: aqueous, 76.81 ± 61.89 pg/mL; vitreous, 118.53 ± 65.87 pg/mL; subretinal fluid, 1636.58 ± 356.47 pg/mL; and plasma, 74.64 ± 43.94 pg/mL. There was a statistical difference between the study and the control group (P < 0.001) in the aqueous and vitreous samples.

CONCLUSION

Stage 5 retinopathy of prematurity has elevated intraocular levels of vascular endothelial growth factor, which remains high despite severe retinal lesion. There was no statistical difference in plasma levels of the molecule between the control and study group.

Reduction of fluence to decrease pain during panretinal photocoagulation in diabetic patients

BACKGROUND AND OBJECTIVE

To assess the effect of laser fluence reduction to reduce pain during panretinal photocoagulation.

PATIENTS AND METHODS

Twenty-five patients (50 eyes) with diabetic retinopathy who had indication for panretinal photocoagulation were included in this prospective, interventional, and comparative study. The right eyes were treated using low fluence parameters (LFP), whereas the left eyes were treated with standard fluence parameters (SFP). At the end of each session, the patient was asked to rate pain from 0 (no pain) to 10 (maximum pain) for each eye (NRS-11 scale). Fluence per burn and total fluence were determined for each eye. Statistical analysis was performed using the Mann-Whitney U test and the Pearson correlation coefficient.

RESULTS

Pain perception (P < .01) and fluence per burn (P < .01) were significantly less using LFP compared with SFP. Pain was proportional to fluence per burn (R(2) = 0.4), but not to number of burns (R(2) = -0.2).

CONCLUSION

The use of LFP seems to be a good option to diminish the pain during panretinal photocoagulation.

Bilateral central retina vein occlusion associated with obesity-hypoventilation syndrome (pickwickian syndrome)

PURPOSE

To describe bilateral central retinal vein occlusion (CRVO) as a clinical manifestation of obesity-hypoventilation syndrome (pickwickian syndrome).

METHOD

Case report.

PATIENT

A 37-year-old Hispanic man with morbid obesity and obstructive sleep apnea who suddenly developed bilateral loss of vision.

RESULTS

Laboratory studies disclosed the following: hematocrit, 81%; body mass index, 55 kg/m; PaCO2, 52 mmHg; and blood oxygen saturation (SaO2), 54%. Polysomnography demonstrated 45 obstructive apneas and 133 obstructive hypopneas, with abnormal movements of the inferior limbs during sleep.

DISCUSSION

Hypoxia and hypercapnia produce severe erythrocytosis that causes a change in blood viscosity. This may facilitate thrombus formation at the lamina cribrosa of both eyes manifested as bilateral CRVO.

Perfluorocarbon-perfused vitrectomy using a transconjunctival 25-gauge system

PURPOSE

To describe the feasibility of perfluorocarbon-perfused vitrectomy (PCPV) using a 25-gauge system in complicated retinal detachment cases.

METHODS

Thirteen nonconsecutive patients with complicated retinal detachment (either tractional secondary to proliferative diabetic retinopathy or rhegmatogenous) who would not normally be selected for 25-gauge vitrectomy were included in the study. Vitrectomy using 25-gauge ports and perfluorocarbon perfusion was performed. Real vitrectomy time, amount of perfluorocarbon liquid (PCL) used, instrument bending, feasibility of surgical maneuvers using an arbitrary scale, and anatomical and visual results were evaluated.

RESULTS

Real vitrectomy time ranged from 6.2 minutes to 17.1 minutes (mean, 10.3 minutes). Amount of PCL ranged from 8 mL to 40 mL (mean, 24.38 mL). Instruments never bent even when using a wide-angle sutured contact lens. All desired maneuvers could be performed and were facilitated by PCL. All retinas were reattached, with two cases of mild recurrent vitreous hemorrhage. Visual acuity improved in 76.9% of eyes.

CONCLUSIONS

PCPV using a 25-gauge system can be performed, even in complicated cases.

Laboratory screening for zearalenone formation in corn hybrids and inbreds

Grains from 14 corn inbreds and 4 single cross hybrids were inoculated with 3 isolates of Gibberella zeae to determine their inhibition of zearalenone production. The corn hybrids: Pa762 x A632 (50 mg/kg zearalenone production), A619 x A632 (17 mg/kg zearalenone production), H95 x Mo17 (132 mg/kg zearalenone production), and B73 x MO17 (33 mg/kg zearalenone production) appear to have less resistance than the inbreds to toxin formation. Inbred H95 (64 mg/kg zearalenone production) supported the highest toxin production of all inbreds. The remaining 13 inbreds did not exceed 15 mg/kg zearalenone production. The inbreds A632 (4 mg/kg zearalenone production) and Pa762 (2 mg/kg zearalenone production) demonstrated some resistance; the resulting cross, hybrid Pa762 x A632 (50 mg/kg zearalenone production), does have greater resistance than hybrid H95 x Mo17 (132 mg/kg zearalenone production). Analysis of variance indicated highly significant variation between corn varieties and fungal isolates. The coefficient of variation for 29 fermentations run in duplicate on inoculated control corn to produce zearalenone (212 mg/kg) was 37%, which would include variation in both the fermentation and analysis. Isolate and variety interaction is not significant.