OBJECTIVE : To assess whether ocular compression preintravitreal
bevacizumab injection is beneficial in reducing the
post-intravitreal injection intraocular pressure (IOP).
METHOD : A prospective randomised, two-arm parallel control
trial, at a secondary care ophthalmology clinic (Witbank
Provincial Hospital) was conducted. Fifty-six patients receiving
intravitreal injections of 0.1 ml bevacizumab (Avastin, Genentech,
Roche, Basel, Switzerland) were randomised to either receive no
intraocular pressure-lowering intervention pre-injection, or to
receive intraocular pressure-lowering intervention pre-injection
with the application of a Honan balloon inflated to 20–30 mmHg
and applied over the eye for 15 minutes. After the administration
of intravitreal injection in either group, the patients’ intraocular
pressures were measured at 5-, 10- and 30-minute intervals
using the Goldmann applanation tonometer.
RESULTS : Twenty-eight patients were enrolled in each of the
intervention and control arms of the study. The median baseline
IOPs were 14 mmHg (IQR: 11–18 mmHg) and 14 mmHg (IQR:
12–16.5 mmHg) (p=0.914) in the control and intervention group
respectively. The median IOPs in the control and intervention
groups at 5-, 10- and 30-minutes respectively were 36 mmHg
(IQR: 33–38 mmHg) and 18 mmHg (IQR: 16–24 mmHg) (p<0.001); 29
mmHg (26–30 mmHg) and 18 mmHg (14–20 mmHg) (p<0.001); and
24 mmHg (20–26 mmHg) and 18 (12–18 mmHg) (p<0.001).
CONCLUSION : The results demonstrate a significant reduction
in the post-injection IOP rise with the use of a Honan balloon to
reduce IOP prior to the administration of intravitreal injections.
Based on the findings of this study it is recommended that
the Honan balloon be used prior to intravitreal injections in
patients with normal pre-injection IOPs.