Fluid monitor in neovascular age-related macular degeneration: a case report
Title: Fluid monitor in neovascular age-related macular degeneration: a case report
Valentina Sarao , MD
Daniele Veritti, MD
Paolo Lanzetta, MD
Department of Medicine-Ophthalmology, University of Udine, Udine, Italy
Age-related macular degeneration (AMD) is a progressive disease that affects the central part of the retina, leading to visual impairment and blindness. Neovascular AMD is characterized by the growth of abnormal blood vessels in the retina, which can cause bleeding, exudation, and scarring. The development of neovascular AMD can lead to severe and irreversible vision loss if left untreated. Anti-VEGF therapy is currently the standard of care for neovascular AMD.
A 68-year-old female presented with a complaint of blurred vision in her left eye for the past two weeks. She had a history of hypertension and hyperlipidemia but was otherwise healthy. On examination, her best-corrected visual acuity (BCVA) was 68 letters in the left eye and 82 letters in the right eye. Her intraocular pressure was normal in both eyes. The fundus examination of the left eye revealed a juxtafoveal small pigment epithelium detachment (PED) with associated subretinal fluid (SRF). The optical coherence tomography (OCT) scan showed a central retinal thickness of 331 μm. Fluorescein angiography and indocyanine green angiography revealed a type 1 macular neovascularization. The patient was thus diagnosed with neovascular age-related macular degeneration (AMD) and was started on intravitreal injections of ranibizumab using a 3-monthly injection scheme followed by bimonthly injections for the first year. RetInSight Fluid Monitor is the first AI-based fluid activity meter for the monitoring of disease progression and treatment response in patients with neovascular AMD in clinical routine. It provides an automated measurement of the volume of intraretinal fluid (IRF), SRF, and PED within the 1 mm Early Treatment Diabetic Retinopathy Study (ETDRS) grid and 6 mm ETDRS grid. In our case report, the “Fluid Monitor report” provided by the RetInSight Fluid Monitor showed at the baseline a volume of 79.28 nl SRF and 14.27 nl PED within 1 mm and 209.03 nl SRF and 172.43 nl PED within 6 mm (Figure 1). This information was useful in monitoring the response to treatment and the resolution of SRF and PED in the patient’s left eye during the course of the intravitreal treatment (Figure 2). After three monthly doses of intravitreal ranibizumab, the RetInSight Fluid Monitor showed that the SRF had completely disappeared, and the PED volume had reduced in the left eye to 13.98 nl and 124 nl, respectively, within 1 and 6 mm ETDRS grid. The patient also reported an improvement in visual acuity, which increased from 68 letters to 70 letters. During the follow-up, the RetInSight Fluid Monitor showed that the SRF and PED volumes had increased in the left eye and visual acuity was 77 letters after one year of treatment. Interestingly, until 7 months of bimonthly treatment with intravitreal ranibizumab, the RetInSight Fluid Monitor showed that the SRF was not visible within the 1 mm ETDRS grid, while there was an increase in volume within the 6 mm ETDRS grid. Despite this increase in fluid volume, the patient’s visual acuity continued to improve and reached 80 letters at 7 months, suggesting that the treatment was still effective in managing the neovascular AMD (figure 3). These findings suggest that monitoring fluid volume within the 6 mm ETDRS grid alone may not provide a complete picture of treatment response. It is important to consider the fluid volume within both 1 and 6 mm ETDRS grid.
The use of the RetInSight Fluid Monitor was useful in monitoring the response to treatment and the resolution of SRF and PED in the patient’s left eye during the course of the intravitreal treatment. The information provided by the RetInSight Fluid Monitor was helpful in assessing the effectiveness of the intravitreal ranibizumab treatment and in determining whether additional intervention or drug switching was necessary.