Outpatient Ultra wide-field intravenous fundus fluorescein angiography in infants using the Optos P200MA scanning laser ophthalmoscope

Fundus fluorescein angiography imaging of retinopathy of prematurity in infants: A review

Fluorescein angiography in retinopathy of prematurity is increasingly utilized over the past decade. The development of ultra-wide-field imaging combined with fluorescein angiography has allowed improved visualization of the peripheral retinal vasculature. Patient cooperation in the pediatric population is particularly challenging, but hand-held digital retinal photography has shown promise and can visualize the infant retina without the need for anesthesia and intravenous access. Many features of retinopathy of prematurity and its response to laser and anti-VEGF treatment can be either exclusively or better visualized on fluorescein angiography compared to indirect ophthalmoscopy or color fundus photography. Disease treatment is gradually shifting from laser photocoagulation to intravitreal anti-VEGF agents, the latter being associated with late-onset vision-threatening sequelae. The role of fluorescein angiography in retinopathy of prematurity monitoring will continue to increase with the longer follow-up required and different clinical behavior seen with anti-VEGF treatment. We highlight the utility, safety, and importance of fluorescein angiography in the diagnosis, treatment, and follow-up of retinopathy of prematurity.

Understanding the relationship between visual-angle and eye-angle for reliable determination of the field-of-view in ultra-wide field fundus photography

Visual-angle has been used as the conventional unit to determine the field-of-view (FOV) in traditional fundus photography. Recently emerging usage of eye-angle as the unit in wide field fundus photography creates confusion about FOV interpretation in instrumentation design and clinical application. This study aims to systematically derive the relationship between the visual-angle θv and eye-angle θe, and thus to enable reliable determination of the FOV in wide field fundus photography. FOV conversion ratio θe/θv, angular conversion ratio Δθe/Δθv, retinal conversion ratio Δd/Δθv, retinal distance and area are quantitatively evaluated. Systematic analysis indicates that reliable conversion between the θv and θe requires determined nodal point and spherical radius of the eye; and the conversion ratio is not linear from the central field to peripheral region. Based on the eye model with average parameters, both angular conversion (Δθe/Δθv) and retinal conversion (Δd/Δθv) ratios are observed to have a 1.51-fold difference at the central field and far peripheral region. A conversion table, including θe/θv, Δθe/Δθv, Δd/Δθv, retinal area and percentage ratio, is created for reliable assessment of imaging systems with variable FOV.

Retinal imaging in infants

Digital retinal imaging is at the core of a revolution that is continually improving the screening, diagnosis, documentation, monitoring, and treatment of infant retinal diseases. Historically, imaging the retina of infants had been limited and difficult to obtain. Recent advances in photographic instrumentation have significantly improved the ability to obtain high quality multimodal images of the infant retina. These include color fundus photography with different camera angles, ultrasonography, fundus fluorescein angiography, optical coherence tomography, and optical coherence tomography angiography. We provide a summary of the current literature on retinal imaging in infants and highlight areas where further research is required.

ULTRA-WIDE-FIELD IMAGING AND INTRAVENOUS FUNDUS FLUORESCEIN ANGIOGRAPHY IN INFANTS WITH RETINOPATHY OF PREMATURITY

PURPOSE

To determine the feasibility of ultra-wide-field imaging and ultra-wide-field intravenous fundus fluorescein angiography (UWF-IV-FFA) in infants with retinopathy of prematurity (ROP) using Optos 200Tx.

METHODS

We performed Optos 200Tx capturing on 32 premature infants (14 females) and UWF-IV-FFA with Optos 200Tx on 12 of the 32 infants between April 2017 and July 2018 at the affiliated eye hospital of Wenzhou Medical University and analyzed their fundus images.

RESULTS

Ultra-wide-field color images were acquired from 32 infants (64 eyes). UWF-IV-FFA was performed successfully in 12 premature infants (24 eyes). No adverse events were observed. The ultra-wide-field Optos 200Tx color images and UWF-IV-FFA images revealed Stages 1, 2, and 3 ROP and aggressive posterior ROP.

CONCLUSION

Ultra-wide-field imaging and intravenous fundus fluorescein angiography using Optos 200Tx are feasible in infants with ROP, which have the potential to screen, diagnose, and follow-up for ROP.

Clinic-based ultra-wide field retinal imaging in a pediatric population

Background

Pediatric retinal disorders, although uncommon, can be challenging to assess in the clinic setting and often requires an exam under anesthesia. The purpose of our study was to evaluate the use of ultra-wide field retinal imaging in children without sedation in an outpatient clinic.

Methods

We performed a retrospective case series of patients 18 years or younger who received ultra-wide field imaging over a one year period. The age, gender, and clinical course were documented. Color fundus and red-free images were reviewed to assess field of view. Ultra-wide field autofluorescence (UWF-FAF) was evaluated for abnormal autofluorescence patterns and ultra-wide field fluorescein angiography (UWF-FA) was assessed for angiographic phase and field of view.

Results

A total of 107 eyes of 55 patients with a mean age of 11.1 years (SD 3.7 years, range 3–18 years) were evaluated. Twenty-seven (49%) patients were male. The most common diagnosis was retinopathy of prematurity (7 of 55 patients, 12.7%) followed by trauma (7.4%), Coats disease (7.4%), and rhegmatogenous retinal detachment (7.4%). The number of quadrants visualized anterior to the equator correlated with patient age (r = 0.4, p < 0.01). On UWF-FA, 6 of 14 patients (43%) had images of the arterial phase captured and 14 of 14 patients (100%) had images of the venous phase or later captured.

Conclusions

We demonstrated that UWF imaging is obtainable in children as young as 3 years old without sedation. UWF fundus photography, UWF-FAF and UWF-FA were useful clinical adjuvants to examination and provide additional information for documenting and monitoring pediatric retinal diseases.

Ultra-Widefield Imaging for Pediatric Retinal Disease

This article explores the development of retinal imaging, with particular emphasis on ultra-widefield imaging and the key concept of field of view. Two ultra-widefield imaging platforms are examined in detail-Optomap and Spectralis-noncontact imaging systems that include protocols for performing angiography in infants. Applications of ultra-widefield imaging are illustrated using case studies, including diagnosis, monitoring, and screening.

Ultra-widefield fundus imaging in gas-filled eyes after vitrectomy

Background

To evaluate the quality of the images obtained by an ultra-widefield device in gas-filled eyes after vitrectomy for a retinal detachment.

Methods

Retrospective case series. The ultra-widefield scanning laser ophthalmoscopic images (Optos 200Tx imaging system) of 40 eyes that were gas-filled with 40 to 90% of the vitreous cavity after vitrectomy for a rhegmatogenous retinal detachment were studied. The rates of detecting the rates of reattachments and the causative retinal tears that were treated and were in the superior or inferior areas in eyes with intravitreal gas of ≥60% were compared to that to eyes with intravitreal gas of <60% of the vitreous cavity. The widefield images recorded with 532 nm (green) or 633 nm (red) wavelength laser lights were compared to determine which wavelength had clearer images in 20 eyes of retinal detachment with superior retinal tears and were more than 50% gas-filled.

Results

The ultra-widefield images showed a retinal reattachment in all eyes on postoperative days 1 to 40 (mean; 8.7 ± 7.5 days). A superior retinal break was not visible in 5 of 26 eyes due to a reflection from the intravitreal gas bubbles when the gas was <60%. However, the superior retinal breaks were visible when the patients were requested to gaze downward to reduce the reflection of the gas bubble. The retinal breaks treated with laser burns and the retinal vasculature were imaged better with green laser than red laser light, and the choroidal vasculature was seen better with red laser light.

Conclusions

Ultra-widefield fundus images can be used to evaluate and document the retinal breaks and retinal reattachments in gas-filled eyes. The green and red laser lights can image different depths of the retina and choroid in gas-filled eyes.

Avascular Retinal Findings in a Child With Achondroplasia

The authors present clinical and angiographic findings in a 12-year-old girl with achondroplasia who presented with bilateral retinal peripheral nonperfusion and unilateral rhegmatogenous retinal detachment, which has not been previously described in achondroplasia. This report contributes incremental knowledge regarding aberrant retinal vascular phenomena observed in pediatric disease states and implicates the possible role of mutations in the FGFR3 gene in peripheral vascular abnormalities. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:272-274.].

Non-contact ultra-widefield retinal imaging of infants with suspected abusive head trauma

PurposeThe purpose of the study was to audit the use of non-contact ultra-widefield retinal imaging in infants with suspected abusive head trauma (AHT) using the Optos P200MA Scanning Laser Ophthalmoscope.Patients and methodsA retrospective, observational case series. Ten eyes of five consecutive infants (aged 1-15 months) with suspected (or in 1 case, known) AHT referred for an ophthalmological opinion were included. Each infant underwent non-contact ultra-widefield retinal imaging using the Optos P200MA scanning laser ophthalmoscope. Optos fundus fluorescein angiography (FFA) was performed in one infant with oral sedation. The other four infants did not require sedation. The main outcome measure was the acquisition of a single, definitive ultra-widefield retinal image in each eye. Safety was audited by determining adverse changes in heart rate and oxygen saturations that required cessation of imaging.ResultsThe Optos P200MA ultra-widefield scanning laser ophthalmoscope acquired good quality retinal images in all infants. Documentation of acute, widespread retinal haemorrhages contributed to a diagnosis of AHT in three infants. Chronic pre-macular haemorrhage and macular schisis were documented by FFA in a fourth infant. The absence of retinal haemorrhages was documented in a fifth infant contributing to the exclusion of a diagnosis of AHT. There were no adverse safety signals in any infant in this series.ConclusionThe Optos P200MA ultra-widefield scanning laser ophthalmoscope appears safe to use in infants with suspected AHT, providing high-quality retinal images in a single frame without ocular contact. Optos P200MA may be used as alternative to RetCam to document retinal haemorrhages in stable infants with suspected AHT.

Anti-VEGF treatment and peripheral retinal nonperfusion in patients with central retinal vein occlusion

Purpose

To evaluate the association between the size of peripheral retinal nonperfusion and the number of intravitreal ranibizumab injections in patients with treatment-naïve central retinal vein occlusion (CRVO).

Methods

Fifty-four patients with treatment-naïve CRVO and macular edema were included. Each patient underwent a full ophthalmologic examination including optical coherence tomography imaging and ultrawide-field fluorescein angiography. Monthly intravitreal ranibizumab injections were applied according to the recommendations of the German Ophthalmologic Society. Two ophthalmologists quantified the areas of peripheral retinal nonperfusion (group 1= less than five disc areas, group 2= more than five disc areas). Correlation analyses between the size of nonperfusion with best-corrected visual acuity, central subfield thickness, and the number of intravitreal injections were performed.

Results

Best-corrected visual acuity improved significantly after intravitreal injections (P<0.001, both groups). Final central subfield thickness after treatment did not significantly differ between both groups (P=0.92, P=0.96, respectively). Mean number of injections in group 1 and group 2 was 4.12±2.73 and 9.32±3.84, respectively (P<0.001). There was a significant positive correlation between areas of nonperfusion and the number of injections in each group. (R=0.97, P<0.001; R=0.94, P<0.001, respectively).

Conclusion

Peripheral retinal nonperfusion in patients with CRVO correlates significantly with the number of needed intravitreal ranibizumab injections. Ultrawide-field fluorescein angiography is a useful tool for detection of peripheral retinal ischemia, which may have direct implications in the diagnosis, follow-up, and treatment of these patients.

ULTRA-WIDEFIELD FUNDUS IMAGING: A Review of Clinical Applications and Future Trends

PURPOSE

To review the basic principles of ultra-widefield fundus imaging and discuss its clinical utility for a variety of retinal and choroidal disorders.

METHODS

A systematic review of the PubMed database was performed using the search terms Optos, optomap, panoramic, ultra-widefield, wide-angle, and ellipsoid mirror. This yielded 158 publications of which 128 were selected based on content and relevance.

RESULTS

A total of 128 articles pertaining to ultra-widefield imaging were cited in this review.

CONCLUSION

Optos ultra-widefield imaging has become an essential tool for the identification of peripheral retinal and vascular pathology. The high resolution and multimodal capabilities of this device are also providing new insights into a variety of disorders, even those that primarily involve the posterior pole. Although the presence of artifact and the need for clinical validation are significant hurdles to more widespread use, ultra-widefield is evolving to become the standard-of-care imaging modality for many diseases and is finding new clinical and research applications such as for screening and telemedicine.

Heidelberg Spectralis ultra-widefield fundus fluorescein angiography in infants

PURPOSE

To describe the intraoperative use of the Heidelberg Spectralis for ultra-widefield fundus fluorescein angiography in infants.

DESIGN

Retrospective observational case series.

METHODS

A modified Heidelberg Spectralis was used to perform ultra-widefield fundus fluorescein angiography in infants undergoing an examination under general anesthesia for a range of retinal vasculopathies. Peripheral angiographic findings, angiographic image acquisition time, and any complications were reviewed.

RESULTS

A total of 22 eyes of 11 infants underwent intraoperative ultra-widefield fundus fluorescein angiography using the modified Heidelberg Spectralis. Ultra-widefield fundus fluorescein angiography was successfully performed in all infants and permitted capture of the posterior pole as well as the peripheral retina in a single shot centered on the macula. Peripheral retinal pathologies captured include neovascularization, capillary nonperfusion, and skip areas from previous laser treatment. Capturing of angiographic images took a mean time of 7.09 minutes. Image artifact from condensation of the ultra-widefield lens was noted during imaging of 1 infant.

CONCLUSIONS

The modified Heidelberg Spectralis is an effective and reliable imaging tool for performing ultra-widefield fundus fluorescein angiography in infants. It is capable of capturing wide-angle images of high quality. The technique has advantages as an alternative to RetCam fluorescein angiography in infants undergoing an examination under general anesthesia.