Intravitreal bevacizumab (Avastin) treatment is safe in terms of intraocular and blood pressure

Editor, Several therapeutic substances targeted against vascular endothelial growth factor (VEGF) are available for the treatment of ophthalmological diseases at present. One is bevacizumab (Avastin), a substance that can be applied either systemically (Michels et al. 2005) or locally (Rosenfeld et al. 2005). With regard to side-effects, it is well known that systemic bevacizumab can cause an increase in blood pressure (BP), including in non-cancer patients (Michels et al. 2005), and that some intravitreal injections such as triamcinolone may cause a detrimental rise in intraocular pressure (IOP) (Jonas et al. 2003). Therefore we investigated the safety of intravitreal bevacizumab injections in terms of IOP and BP. We obtained informed consent from 45 patients undergoing bevacizumab injections. Intraocular pressure and BP were measured before, immediately after, and at 1, 3, 6 and 24 hours and 2, 6 and 12 weeks after the injection. Any patients with prior surgeries or glaucoma were excluded. Injection of 1.25 mg bevacizumab was performed at the lower pars plana with a sharp 27-gauge needle after complete sterile draping and rinsing with topical povidone-iodine (Binder et al. 1999) under topical anaesthesia with Tetracain 1% eyedrops. All additional manipulation such as the subconjunctival injection of anaesthetic or application of pressure by forceps was avoided. Manual measurements of BP and IOP by Goldmann applanation tonometry were performed. Mean baseline (before the injection) IOP was 13.9 ± 2.6 mmHg (mean ±standard deviation; range 9–20 mmHg). Intraocular pressure immediately after the injection was 14.5 ± 4.4 mmHg (range 9–28 mmHg). Subsequent IOP values were: 13.6 ± 3.4 mmHg at 1 hour; 12.9 ± 2.9 mmHg at 3 hours; 13.0 ±3.1 mmHg at 6 hours; 12.7 ± 3.1 mmHg at 24 hours; 12.7 ±3.0 mmHg (range 8–23 mmHg) at 2 weeks; 13.8 ± 2.8 mmHg (range 9–20 mmHg) at 6 weeks, and 14.7 ±2.9 mmHg (range 9–19 mmHg) at 12 weeks after the injection. None of the postoperative measurements differed significantly from the preoperative values. Directly after the injection only two patients showed IOP values over the normal range (< 22 mmHg), one at 22 mmHg and one at 28 mmHg. No IOP-lowering medication was necessary and no late increase was observed (Fig. 1). Intraocular pressure (IOP) course after a single 1.25-mg/0.05-ml intravitreal injection of bevacizumab. The boxplot depicts the 50% interquartile range of (IOP) among the subjects. The heavy black line is the median value; the bars show the range of the data with the outliers beyond the 10/90th percentile shown as circles. Baseline BP values were systolic 146 ± 20 mmHg (range 110–185 mmHg) and diastolic 81 ± 9 mmHg (range 65–95 mmHg). In total 82% of the patients were on at least one medication for high BP. The changes in systolic and diastolic BP are shown in Fig. 2. None of the systolic BP values differed significantly from preoperative values. The 1-hour (p = 0.04) and 6-hour (p = 0.01) diastolic BP values were significantly lower than before surgery. This may reflect physiological diurnal changes or a response to the easing of surgery-related stress. Either way, no increase in BP was observed over the 3-month period of the investigation, which might be expected as a theoretically adverse response to anti-VEGF treatment. Blood pressure course after a single 1.25-mg intravitreal injection of bevacizumab. In summary, the data for our case series indicate that injection of 0.05 ml (1.25 mg) bevacizumab intravitreally is safe in terms of BP and IOP in the short term. Therefore, the necessity for postoperative IOP checks, which are considered especially important if the procedure is performed in an outpatient clinic, is not supported by our data for bevacizumab and may be questioned.