Short-time intraocular pressure changes after intravitreal applications and relationship with anterior chamber depth

PURPOSE: To evaluate the short-term impact of intravitreal injection on IOP and ACD and to assess whether there is any correlation between IOP and ACD. MATERİAL AND METHODS: One hundred and eighteen eyes of 105 patients who were intravitreal ranibizumab administered diagnosis of wet age-related macular degeneration, diabetic macular edema, macular edema secondary to venous occlusion at Celal Bayar University Hafsa Sultan Hospital, Department of Ophthalmology Retina unit. A detailed ophthalmologic examination was performed. All patients were examined by optical coherence tomography, fundus flourescein angiography for macular edema. Intraocular pressure of patients was measured immediately before intravitreal injections with Tono-Pen Avia (Reichert) contact tonometer by taking the average value of three measurements. Anterior chamber depth and axial length of patients patients was measured immediately before intravitreal injections with Lenstar LS 900 (Haag Streit) by taking the average value of five measurements. Intravitreal injections were performed under sterile conditions. Intraocular pressure of patients was measured after intravitreal injections of 5, 15, 30 minutes, and the first day with Tono-Pen Avia (Reichert) contact tonometer by taking the average value of three measurements. Anterior chamber depth and axial length of patients patients was measured after intravitreal injections of 5, 15, 30 minutes, and the first day with Lenstar LS 900 (Haag Streit) by taking the average value of five measurements. In our study, IOP elevation after intravitreal injection, when the rise in returns to normal values, whether there is any correlation between IOP and ACD, whether there is any differences between axial lengths or anterior chamber depths of different ones and phakic and pseudophakic eyes. RESULTS: 55 of the patients were female and 63 were male. The diagnoses for which intravitreal injection of ranibizumab was performed were as follows: diabetic macular edema (88) wet age-related macular degeneration (23), branch retinal vein occlusion (6), central retinal vein occlusion (1). 95 eyes were phakic and 23 were pseudophakic. Patients were classified three distinct groups according to the axial length (AU) of the eyes (AU<22 mm, 22-24 mm AU, AU>24 mm). Patients were classified three distinct groups according to anterior chamber depths (ACD) of the eyes (ACD<2,5 mm, ACD 2,5-3,5 mm, ACD> 3,5 mm). Five minutes after the injection, mean IOP increased 24.15 ± 10.12 mmHg from 15.03 ± 2.86 mmHg and the difference was statistically significant (p<0,05). Fifteen minutes after the injection, mean IOP was 17.02 ± 5.25 mmHg, compared with baseline values the difference was statistically significant (p<0,05). Thirty minutes after the injection, IOP returned to baseline values. Five minutes after the injection, mean ACD decreased 2,90 ± 0,84 mm from 2,9498 ± 0,8957 mm and the difference was statistically significant (p<0,05). One day after the injection, ACD returned to baseline values. There was no statistically significant difference for IOP and ACD measurements between the three groups who were classified according to the axial length of the eyes (p>0.05, Kruskal-Wallis test). There was no statistically significant difference for IOP measurements between the three groups who were classified according to the anterior chamber depth of the eyes (p> 0.05, Kruskal-Wallis test). The IOP differences between phakic and pseudophakic eyes at all time points were not statistically significant (p>0.05). However, there was statistically significant difference for ACD measurements at all time points between phakic and pseudophakic eyes(p<0,05). There was a weak correlation between ACD and IOP at all time points. CONCLUSİON: Intravitreal injection causes a considerable short-term transient rise in IOP. IOP rises correlated with shallow ACD, over time IOP decreases and ACD deepens. In our study, increases in IOP after injection of about 30 minutes, returned to baseline values. On the basis of these findings, patients should be carefully monitored for at least 30 minutes after intravitreal injection. Increases in intraocular pressure back to normal in most patients in the first hour after injection particularly in the short axial length of the eyes, ocular vascular problems and advanced very high IOP in glaucoma increases after intravitreal injection paracentesis should be considered. KEYWORDS: Intravitreal injection, Intraocular pressure, Anterior chamber depth, Ranibizumab.