Abstract
Purpose :
Delivery of pharmaceuticals into the suprachoroidal (SC) space, a potential space between the choroid and sclera, is a promising approach to the management of retinal diseases. A deeper understanding of alterations induced in the SC space is needed following suprachoroidal delivery in humans.
Methods :
Subjects in the prospective HULK trial (IND 115683; NCT02949024) receiving SC triamcinolone acetonide (0.1 cc, 4 mg, CLS-TA, Clearside Biomedical) for diabetic macular edema (DME) were imaged with anterior segment spectral-domain optical coherence tomography (AS-OCT). When imaged, line (15°, 768 A-scans) & volume (15° x 5°, 41 sections, 768 A-scans) scans of 8 pre-defined quadrants were captured. AS-OCT were obtained before & 30 minutes following SC CLS-TA. SC width was measured using calipers (Figure). A 1:1 pixel to micron ratio was applied.
Results :
AS-OCT of study (n=14) & fellow eyes (n=10) (no SC injection) were captured from 17 visits. Among all subjects, mean time from last SC delivery to final AS-OCT was 4.8 (range: 1.0 – 9.9) months. At the final imaging session, SC width was not significantly different in study eyes (8.4 µm) compared to fellow eyes (8.1 µm) (P=0.698). Three imaging sessions, involving 2 patients, were performed at the time of SC CLS-TA delivery: prior to CLS-TA delivery, mean SC width was 9.9 µm, and mean SC width increased by a mean of 65.1 µm to 75.1 µm (P<0.001) following SC CLS-TA. Mean SC width increased to 17.2 µm, 90.7 µm, 112.3 µm and 56.8 µm at 2, 3, 4, and 5 mm posterior to Schlemm’s canal, respectively. No significant increase in SC width was observed ≤2 mm posterior to Schlemm’s canal (P=0.130). Mean SC width returned to 14.9 µm at follow-up 1 month later (P=0.221).
Conclusions :
SC injection of CLS-TA in eyes of patients with DME resulted in measurable expansion of the width of the SC space within 30 minutes. By 1 month after delivery, the SC width had normalized & no anatomic differences were observed compared to fellow eyes used as controls.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.