Supraciliary effusions and ciliary body thickening after scleral buckling procedures

The purpose of the study was to use ultrasound biomicroscopy to identify and quantity changes in anterior segment parameters after scleral buckling procedures.

Ultrasound biomicroscopy was used to examine 15 patients with retinal detachment within 1 week before and after surgery. Quantitative measurements were performed of anterior chamber depth, supraciliary effusion depth, ciliary body thickness, and angle opening.

Supraciliary fluid was present after surgery in 12 patients (80%). Average supraciliary fluid depth was 0.16 +/- 0.13 mm. Ciliary body thickness measurements at a point 2-mm posterior to the scleral spur increased after surgery in all patients an average of 0.15 +/- 0.10 mm. There was a strong correlation between ciliary fluid levels and change in ciliary body thickness (r = 0.742, P < 0.01). Anterior chamber depth decreased after surgery in 14 patients (93%). A decrease of angle opening of greater than 5 degrees was noted in 11 patients (73%). In all of these 11 patients, the ciliary body and iris root were considered to be rotated anteriorly. Six (55%) of 11 of these patients showed anterior bowing of the iris, indicating pupillary block. Complete angle closure occurred over one to three quadrants in three patients, but none of these patients had complete angle closure or glaucoma.

Supraciliary effusions and ciliary body thickening are common after scleral buckling procedures and can produce conditions conducive to angle closure. Angle narrowing occurs through a combination of direct anterior iris rotation and induced pupillary block.