Imaging Characteristics and Clinical Utility of Full-Dose vs Quarter-Dose Ultra-Widefield Fluorescein Angiography

Abstract

Purpose : In the spring of 2022, the United States faced a nationwide shortage of fluorescein, impacting medical imaging facilities. In response, the Cleveland Clinic adjusted its protocol initially utilizing a reduced half dose(250mg) of sodium fluorescein(10%) for patients requiring ultra-wide fluorescein angiography. Given the prolonged shortage, a quarter dose(125mg) of sodium fluorescein(10%) has been implemented as a solution to meet patient needs efficiently. This study was designed to assess differences in image quality and clinical utility between quarter dose and full dose fluorescein in ultra-wide fluorescein angiography for a cohort of stable patients.

Methods : This was an IRB approved, retrospective review of patients with retinal vascular disease. Patients were included in the study if they had undergone both full-dose and follow-up quarter-dose ultra-wide fluorescein angiography at the Cole Eye Institute. Vascular leakage from ultra-wide fluorescein angiography images was quantitatively graded using a machine-learning-enhanced automated segmentation platform. Leakage areas measured included three fovea centered rings of increasing diameter(fovea inner, fovea middle and fovea outer area). Scores were then compared between quarter-dose and full-dose images. Image quality and leakage were also assessed by a masked independent reviewer. Side effects after fluorescein administration were recorded for each patient and compared between groups.

Results : 74 eyes of 37 patients were included in this study. 32 patients had uveitis, 4(10%) diabetic, and 1(2%) other diagnosis. Automated full vs quarter dose leakage analysis revealed no significant differences with the mean fovea inner area leakage measuring 8.45%±0.16 for full dose(FD) and 6.67%±0.1 for quarter dose(QD). Mean fovea middle area leakage measured 9.63%±0.14 (FD) compared to 9.58%±0.11 (QD). Finally, mean fovea outer area leakage was 9.70%±0.10 (FD) vs 8.95%±0.09 (QD). UWFA images were deemed of equal quality and leakage by the independent masked reviewer. Side effects included nausea in both groups.

Conclusions : Within this cohort, the use of a quarter dose of UWFFA yielded similar outcomes in both automated leakage image metrics and masked image quality review when compared to the full dose. Utilizing a quarter dose appears to be a reliable method for assessing leakage and thus a viable dosage option for UWFFA imaging.

This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.