title: Effect of prophylactic timolol 0.1% gel on intraocular pressure after an intravitreal injection of ranibizumab: a randomized study.
abstract: OBJECTIVE
  The purpose of this study is to make a prospective evaluation of the effect of timolol 0.1% eye gel on short-term intraocular pressure (IOP) after an intravitreal injection (IVI) of ranibizumab.
  
  
  METHODS
  One hundred and fifty eyes of 150 IVI-naïve patients with macular edema caused by various pathological conditions (age-related macular degeneration, central or branch retinal vein occlusion, and diabetic retinopathy) were scheduled to undergo an IVI of ranibizumab (0.5 mg/0.05 cc). The patients were randomly divided into three groups: 50 were not treated with timolol before the IVI (group 1); 50 received an instillation of timolol 0.1% eye gel the evening before the IVI (group 2); and 50 received an instillation of timolol 0.1% eye gel 2 hours before the IVI (group 3). The incidence of clinically significant intraocular hypertensive spikes (>25 mmHg and >40 mmHg) was then assessed.
  
  
  RESULTS
  Our findings showed that mean IOP at baseline was significantly higher than at both 5 and 60 minutes after IVI (P<0.01). Spikes of >25 mmHg were recorded at either time in 27 patients (54%) in group 1, 23 patients (44%) in group 2, and 24 patients (48%) in group 3. None of the between-group differences were significant. Spikes of >40 mmHg (which were only detected 5 minutes after IVI) were recorded in nine (18%), eight (16%), and one patient (2%) in groups 1, 2, and 3, respectively. The only significant difference was between the control and group 3 (P=0.012).
  
  
  CONCLUSIONS
  An increase in IOP after antivascular endothelial growth factor IVI is a frequent complication. The prophylactic use of timolol 0.1% gel effectively reduced the mean IOP when administered 2 hours before IVI and was also effective in preventing dangerous IOP spikes of >40 mmHg. It is therefore recommended before IVIs as a means of preventing emergency procedures and preserving the health of the optic nerve.
authors.affiliation: Eye Clinic, Melegnano Hospital, Vizzolo Predabissi, Italy.
authors.forename: Alfredo
authors.initials: A
authors.lastname: Pece
authors.affiliation: Eye Clinic, Melegnano Hospital, Vizzolo Predabissi, Italy.
authors.forename: Davide
authors.initials: D
authors.lastname: Allegrini
authors.affiliation: Eye Clinic, San Paolo Hospital, Università di Milano, Milano, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Montesano
authors.affiliation: Eye Clinic, Melegnano Hospital, Vizzolo Predabissi, Italy.
authors.forename: Andrea Fabio
authors.initials: AF
authors.lastname: Dimastrogiovanni
keywords: anti-VEGF therapy; macular edema; pressure spikes; pressure-lowering medication