Figure 3.

Intraoperative pressure levels for bleb propagation. (A) The maximum injection pressures, recorded in pounds per square inch (psi), for pre-bleb formation were determined for 63 (90%) out of the 70 patients receiving pneumatic-assisted subretinal gene therapy and compared across seven retinal degenerative conditions with no differences noted. (B) The volumes of balanced salt solution (BSS) injected were compared across conditions for 60 (85.7%) out of the 70 patients with no differences noted. The volumes used were determined by the surgeon. Note that no patients with condition C had BSS pre-blebs. (C) The maximum injection pressures for BSS pre-bleb formation (N=63) were then stratified by patient age. There was no difference across the four age groups. (D) Maximum vector propagation injection pressures were recorded for 68 (97.1%) of the 70 patients and stratified by age. The youngest patients (4–20 years) required significantly greater pressures for vector propagation than the oldest group (>55 years). One-way analysis of variance (ANOVA) testing was performed with post-hoc analysis for comparison across conditions (A-B) or age ranges (C-D). Significance was defined as p<0.05.