Quantitative evaluation of retinal microvasculature and retrobulbar vessels after intravenous chemotherapy for retinoblastoma

Assessment of Retinal Microvasculature and Choroidal Vascularity After Intra-arterial Chemotherapy for Retinoblastoma

PURPOSE

To evaluate changes in retinal microvascular density and choroidal vascularity in patients with retinoblastoma (RB) after intra-arterial chemotherapy (IAC).

DESIGN

Retrospective clinical cohort study.

METHODS

This study included 12 unilateral RB eyes treated with IAC (RB tumor), 12 contralateral normal eyes (RB fellow), and 12 healthy controls. The macular retinal thickness and retinal microvascular structure, including the foveal avascular zone (FAZ) area, macular and peripapillary superficial vessel density (SVD), and deep vessel density (DVD), were measured by optical coherence tomography angiography (OCTA). The choroidal thickness (ChT) and choroidal vascularity, including total choroidal area (TCA), luminal area (LA), stromal area (SA), and choroidal vascularity index (CVI), were measured by spectral-domain optical coherence tomography (SD-OCT). A comparison among the 3 groups was conducted, and the correlations among the parameters were analyzed.

RESULTS

Among the 3 cohorts, the foveal retinal thickness, SVD, DVD, ChT, TCA, LA, SA, and CVI were significantly lower in RB tumor compared to RB fellow and the control eyes (all P < .01). There were no significant differences in the parameters between the contralateral and control eyes. The correlation analyses indicated a significant negative correlation between the total melphalan dose and foveal and parafoveal DVD, ChT, and LA.

CONCLUSIONS

The retinal microvascular density and choroidal vascularity were lower in unilateral RB treated with IAC, and seemed to be related to the total melphalan dose. There were no measurable changes in the contralateral eyes.

Optical Coherence Tomography and Optical Coherence Tomography Angiography in Pediatric Retinal Diseases

Indirect ophthalmoscopy and handheld retinal imaging are the most common and traditional modalities for the evaluation and documentation of the pediatric fundus, especially for pre-verbal children. Optical coherence tomography (OCT) allows for in vivo visualization that resembles histology, and optical coherence tomography angiography (OCTA) allows for non-invasive depth-resolved imaging of the retinal vasculature. Both OCT and OCTA were extensively used and studied in adults, but not in children. The advent of prototype handheld OCT and OCTA have allowed for detailed imaging in younger infants and even neonates in the neonatal care intensive unit with retinopathy of prematurity (ROP). In this review, we discuss the use of OCTA and OCTA in various pediatric retinal diseases, including ROP, familial exudative vitreoretinopathy (FEVR), Coats disease and other less common diseases. For example, handheld portable OCT was shown to detect subclinical macular edema and incomplete foveal development in ROP, as well as subretinal exudation and fibrosis in Coats disease. Some challenges in the pediatric age group include the lack of a normative database and the difficulty in image registration for longitudinal comparison. We believe that technological improvements in the use of OCT and OCTA will improve our understanding and care of pediatric retina patients in the future.

Retinal microvasculature observations of fellow eyes after intra-arterial chemotherapy for unilateral retinoblastoma using optical coherence tomography angiography

Purpose

To investigate the characteristics of the retinal microvasculature of the fellow eyes in patients with unilateral retinoblastoma (RB) after intra-arterial chemotherapy (IAC) through optical coherence tomography angiography.

Methods

This retrospective study enrolled 11 fellow eyes of patients with unilateral RB receiving IAC (group I), nine fellow eyes of patients with unilateral RB receiving IAC and intravenous chemotherapy (IVC) (group II), and 14 age-matched normal eyes (control group). Optical coherence tomography angiography was performed on all individuals. Vascular density of superficial capillary plexus and deep capillary plexus (DCP), foveal avascular zone related parameters, and retinal thickness were measured and compared among the three groups.

Results

There was no statistical difference in age and logMAR visual acuity among the three groups. Compared with the control group, the vascular density of the DCP was lower in group I and II. Decreased vascular density of FD-300 and thinner thickness of outer plexus layer to Bruch's membrane were detected in group II compared with the control group. The vascular density and retinal thickness showed no differences between group I and II.

Conclusion

The decreased vascular density in the DCP without measurable visual impairment was observed in fellow eyes after IAC or IAC + IVC for unilateral RB. Further studies with a larger sample would be necessary to determine the clinical significance of these findings.