Postinjection Intraocular Pressure Research Articles

Immediate effect of anti-VEGF injections on optic nerve head: Correlation between intraocular pressure and anatomical peripapillary changes.

This study was designed to investigate retinal nerve fiber layer (RNFL) and radial peripapillary capillaries (RPC) changes on optical coherence tomography (OCT) angiography and OCT thickness alterations associated with acutely increased intraocular pressure after intravitreal injections. This observational clinical study was conducted on 35 eyes (35 patients) with treatment-naïve age-related macular degeneration (AMD) and type 1 or type 2 MNV were enrolled. All patients underwent anti-vascular endothelial grow factor (VEGF) intravitreal injections with 0.05-mL aflibercept (2 mg) between January 2022 and October 2022. Peripapillary OCT angiography perfusion density, retinal nerve fiber layer thickness, and intraocular pressure (IOP) were measured before and immediately after intravitreal injections. In particular, the analysis was performed at the following visits: (T0) 5 to 15 min before the injection of aflibercept; (T1) 2 to 5 min after the injection of aflibercept. Paired t-test was used to compare pre-injection and post-injection values. The mean baseline IOP (T0) value was 17.26 ± 2.4 mmHg and the immediate post-injection IOP (T1) mean value was 34.7 ± 11.50 mmHg (P < 0.01). The mean global RNFL thickness before and immediately after the injection was 100.9 ± 18.8 m and 98.6 ± 17.4 m (P = 0.001). Furthermore, the topographical RNFL analysis showed significant thickness reduction of the nasal and inferior sectors after the procedure when compared to T0 (P = 0.046 and P = 0.001). On the contrary, the mean RCP density changes at T1 did not reach statistically significant (P = 0.636). Furthermore, we found a significant negative correlation between the retinal nerve fiber layer global thickness and the IOP changes (Pearson's correlation = -0.126; P = 0.031). In particular, the nasal RNFL region showed a significant negative correlations with IOP values (Pearson's correlation = -0.198, P = 0,046). We reported acute IOP changes that are associated with reduced RNFL thickness in a group of patients undergoing intravitreal injections of anti-VEGF drugs for neovascular age-related macular degeneration. Moreover, topographical sub-analysis revealed that the nasal RNFL region is most prone to IOP fluctuations. This finding may explain the sudden visual acuity change in patients immediately after injection and may sustain injuries to optic nerve head structures producing glaucomatous damage.

The effect of baseline intraocular pressure and anterior segment parameters on intraocular pressure after intravitreal bevacizumab injection

Purpose We aimed to compare the predictive effect of pre-injection intraocular pressure (IOP) and anterior segment parameters on post-injection IOP values after intravitreal bevacizumab injection for neovascular age-related macular degeneration (NVAMD) in phakic and pseudophakic patient groups. Material and methods This retrospective cross-sectional study included 65 eyes of 65 treatment-naive NVAMD patients. Patients were divided into two groups according to their lens status (35 phakic and 30 pseudophakic patients). Pre-injection IOP, anterior segment parameters measured with PENTACAM, and post-injection IOP values measured at the 5th minute were recorded. Univariate and multivariate regression analyses were used to recognise the predictive effect of pre-injection IOP and anterior segment parameters on post-injection IOP for each group. Results Multivariate regression analyses showed that the decrease in anterior chamber depth (ACD), and the increase in pre-injection IOP were significantly correlated with higher post-injection IOP in the phakic patient group (p = 0.019 and 0.031; respectively). No correlation was found in the pseudophakic patient group. Conclusion Pre-injection ACD and IOP values may be predictive of higher post-injection IOP in phakic patients. Preoperative assessment of these parameters could be beneficial in patients at risk of glaucoma.

Effect of vincristine on intraocular pressure and tear fluid oxidative stress biomarkers in canine transmissible venereal tumor.

The ocular side effects of cancer chemotherapeutic drugs are relatively uncommon. Nonetheless, the ocular system has a potentially high sensitivity to toxic substances. This study proposed a framework to assess the effect of vincristine chemotherapy on intraocular pressure, tear protein, and oxidative stress in canines with transmissible venereal tumor (TVT). The study group comprised 10 dogs with TVT, whose diagnosis was based on cytology, and all dogs were treated with vincristine for 4 weeks. Each animal was given a complete ophthalmic examination, followed by a standard Schirmer tear test. Before and 20 min after administering vincristine, intraocular pressure (IOP) was measured in the eyes with a noncontact tonometer. At any of the times mentioned, tear samples were collected using the Schirmer test procedure and were subjected to protein analysis-oxidative stress index (OSI), total antioxidant capacity (TAC), total oxidant status (TOS), nitric oxide (NO), and malondialdehyde (MDA) were determined, and standard statistical analysis was applied. No significant differences were found in protein in tears, but mean Pre and Postinjection IOP revealed a significant decrease in the eyes each week. Also, results indicated significant differences in oxidative stress markers: increased OSI, NO, and MDA, and reduced TAC. The importance of an increase in oxidative stress levels in the tears of vincristine-treated patients should be taken seriously, as it appears to play a role in the pathogenesis of eye disease. Therefore, during the treatment weeks prior to prescribing vincristine, eye diseases should be evaluated and considered.

Comparison of Intravitreal Dexamethasone Implant and Posterior Subtenon Triamcinolone Injection in the Treatment of Diabetic Macular Edema in Vitrectomized Eyes

Introduction: The aim of this study was to compare posterior subtenon triamcinolone (PSTA) application and intravitreal dexamethasone phosphate (DEX) implant in the treatment of diabetic macular edema (DME) in vitrectomized eyes. Methods: This retrospective study included 64 (48.12%) patients who received PSTA and 69 (51.88%) patients who received DEX implants in DME treatment after vitrectomy. Best corrected visual acuity (BCVA), central macular thickness (CMT), and intraocular pressure (IOP) were analyzed before injection; at 1, 3, and 6 months after injection. The postinjection values were statistically compared with the preinjection value. Results: All postinjection CMT values in both groups were lower than the preinjection value (p < 0.05 for all). There were statistically significant increases in all postinjection BCVAs of the DEX group and postinjection 1-month BCVA of the PSTA group (p < 0.05 for all). However, there was no significant difference in BCVA values of the PSTA group at 3 and 6 months after injection (p > 0.05 for both). There was no statistically significant difference in all postinjection IOP values of the PSTA group (p > 0.05 for all). However, significant increases in IOP were observed in the DEX group at 1 and 3 months after injection (p < 0.05 and p = 0.02, respectively). The number of additional injections between the 3rd and 6th months after the initial injection was statistically higher in the PSTA group (p = 0.006). Conclusion: Both intravitreal DEX and PSTA administration are effective in the treatment of DME after vitrectomy. However, visual improvement persisted longer, and the need for additional injections was less in patients who received DEX.

Intraocular Pressure Elevation Following Intravitreal Anti-VEGF Injections: Short- and Long-term Considerations.

Published studies agree that transient intraocular pressure (IOP) spikes are common after intravitreal injections of anti–vascular endothelial growth factor agents. Currently, there is no standard of care guiding if and when to prevent these IOP spikes. Furthermore, there are challenges in determining the impact of postinjection IOP elevation on the health of the retinal ganglion cells, particularly given the often-existing comorbidities of retinal and glaucoma pathology. This review highlights the current literature regarding both acute and chronic postinjection IOP elevations and discusses management of postinjection IOP elevation, especially in patients at high risk for glaucomatous damage.

The Relationship Between Corneal Biomechanics and Intraocular Pressure Dynamics in Patients Undergoing Intravitreal Injection

A higher "corneal resistance factor" (CRF) was associated with greater intraocular pressure (IOP) elevation after intravitreal injection of bevacizumab. Both higher "corneal hysteresis" (CH) and CRF were associated with more rapid IOP recovery postinjection. The purpose of this study was to evaluate the relationship between measurable corneal biomechanical properties and acute IOP elevation after rapid intraocular volume expansion from the routine intravitreal injection. A total of 100 patients necessitating unilateral intravitreal injection with 0.05 mL of bevacizumab for retinal pathology were analyzed before injection with Goldmann Applanation Tonometry to measure IOP, Ocular Response Analyzer (ORA) to measure corneal biomechanical properties, and optical biometry to calculate globe measurements. IOP and ORA were measured again within 5 minutes of the injection and then IOP measurements were taken every 10 minutes until the IOP was ≤150% of the preinjection IOP. Linear regression and logistic regression were used to test variables associated with acute IOP increase. A Cox proportional hazard model accounting for preinjection IOP and postinjection IOP was used to test the effect of CH or CRF on the time required to return to 150% of baseline IOP. Higher CRF was associated with greater immediate postinjection IOP (P=0.026) elevation. A preinjection IOP>15.5 mm Hg moderately predicted postinjection IOP≥35 mm Hg (area under the receiver operating characteristics curve=0.74). A preinjection IOP>18.5 mm Hg combined with CH poorly predicted postinjection IOP>50 mm Hg (area under the receiver operating characteristics curve=0.67). A higher CH [hazard ratio (HR)=1.24; 95% confidence interval (CI)=1.08-1.42; P=0.002] and preinjection IOP (HR=1.16; 95% CI=1.09-1.22; P<0.001), along with a lower immediate postinjection IOP (HR=0.93; 95% CI=0.90-0.95; P<0.001), were each independently associated with quicker IOP recovery postinjection. Similar results were seen in the Cox model examining CRF and IOP recovery. Higher CRF and preinjection IOP were independently associated with greater postinjection IOP elevations. ORA metrics did not greatly strengthen the prediction of patients who would have postinjection IOP>50 mm Hg. Higher CH and CRF were associated with faster IOP recovery after intravitreal injection, demonstrating the dynamic relationship between ocular biomechanical properties and aqueous outflow pathways.

Rates of RNFL Thinning in Patients with Suspected or Confirmed Glaucoma Receiving Unilateral Intravitreal Injections for Exudative AMD

This study evaluated whether the rate of retinal nerve fiber layer (RNFL) thinning is faster in eyes receiving intravitreal injections than in fellow uninjected eyes among patients suspected of having or confirmed to have glaucoma and exudative age-related macular degeneration (AMD). Retrospective comparative cohort study. Patients with a diagnosis of unilateral exudative AMD and confirmed to have or suspected of having glaucoma in both eyes receiving unilateral intravitreal injections were identified. Those with ≥3 RNFL optical coherence tomography scans and ≥6 injections were included in the study. Rates of RNFL thinning in the injected eye versus the uninjected eye were estimated using linear mixed models. The main outcome measurement was the differences in rates of RNFL thinning in the injected versus the fellow uninjected eye. The effects of postinjection elevation of intraocular pressure (IOP), injection frequency, and number of injections were also evaluated. A total of 53 patients met the inclusion criteria, receiving 26.4 ± 15.9 intravitreal injections. The average rate of RNFL thinning in uninjected eyes was-0.620μm/year (P= .029). Injected eyes had an additional incremental loss of-0.385μm/year, but this value was not statistically significant (95% confidence interval [CI]:-1.147 to 0.379μm/year; P= .324). Subgroup analysis with only glaucoma patients (n= 33) also demonstrated a nonsignificant effect of injections (-0.568μm/year; 95% CI:-1.454 to 0.319μm/year; P= .212). Postinjection IOP elevation, injection frequency, and total number of injections were not associated with faster RNFL loss. Among exudative AMD patients with glaucoma or suspected of having glaucoma, the rate of RNFL thinning in eyes receiving intravitreal injections did not significantly differ from that of fellow uninjected eyes.

Effect of dexamethasone intravitreal implant in vitrectomized and nonvitrectomized eyes of Taiwanese patients with treatment-naïve diabetic macular edema

Vitrectomy may affect intravitreal drug clearance and efficacy for treating diabetic macular edema (DME). This study aimed to evaluate functional and anatomical outcomes of intravitreal dexamethasone (DEX) implant for vitrectomized and nonvitrectomized eyes with treatment-naïve DME in Taiwanese patients. In this retrospective single-center study, we reviewed treatment-naïve patients who received DEX implant monotherapy for center-involved DME from January 2015 to May 2017. Retreatments were provided at least 4 months apart as needed. The primary outcomes included changes from baseline in best-corrected visual acuity (BCVA) and central foveal thickness (CFT) at Month 6. Adverse events were recorded. Twenty-seven eyes in 27 patients had prior vitrectomy and 43 eyes in 41 patients without vitrectomy. Baseline data were comparable. Overall, the improvements in BCVA and CFT were significant by 1 month post-treatment and sustained throughout the study (all p<0.05). At Month 6, BCVA improved by 16.5 and 12.1 letters, and CFT reduced by 138.0 and 121.9μm in vitrectomized and nonvitrectomized eyes, respectively, with a mean of 1.5 DEX implant injection. No significant differences in clinical outcomes were seen between the two groups (all p>0.05). DEX implant injection was well tolerated. About 30% of patients had post-injection intraocular pressure value>20mmHg, and all were manageable with topical hypotensive agents, and no serious ocular complication was observed. In this 6-month retrospective study, intravitreal DEX implant was effective in Taiwanese patients with treatment-naïve DME regardless of vitrectomy status.

Intracameral Bevacizumab versus Subconjunctival Bevacizumab in the Treatment of Neovascular Glaucoma

Purpose: To compare the effect of intracameral Bevacizumab with sub-conjunctival Bevacizumab in the treatment of neovascular glaucoma.&#x0D; Study Design: Quasi Experimental study.&#x0D; Place and Duration of Study: This study was conducted at Civil hospital Karachi, Pakistan from September 2017 to October 2018.&#x0D; Material and Methods: Patients with intractable Neo-vascular glaucoma visiting the outpatient department of civil hospital, Karachi were included in the study and followed up for 8 months. Patients with sulcus or scleral fixation IOLs and those who were treated with vitreoretinal surgeries were excluded. Patients were divided into two groups. Group A included patients treated with intracameral Bevacizumab and in group B, patients treated with sub-conjunctival Bevacizumab were included. Best-corrected visual acuity (BCVA), intraocular pressure (IOP) and neovascularization of the iris (NVI) were compared between the two groups.&#x0D; Results: Thirty-eight eyes were included in the study; 24 (56.7%) right eyes and 14 (43.3%) left eyes. Most of the patients were males with mean age of 54.53 ± 7.2 years. Mean total injection/eye was 3.45 ± 1.73 in group A and 3.12 ± 2.10 in group B. Pre-injection BCVA (log MAR) was 0.48 ± 0.32 in group A and 0.34 ± 0.32 in group B. At 8 months, BCVA was 1.7 ± 0.2 in group A and 0.48 ± 0.34 in group B which were statistically significant. Pre-injection IOP (mmHg) was 48.9 ± 1.8 in group A and 47.34 ± 1.8 in group B. Post-injection IOP was 28.7±0.8 in group A (p = 0.001) and 34.2 ± 3.4 in group B (p = 0.11) at eight months.&#x0D; Conclusion: This study demonstrates that intracameral Bevacizumab significantly improves BCVA and controls IOP in neovascular glaucoma. However, sub-conjunctival Bevacizumab significantly improves BCVA but decrease in IOP is not statistically significant.

Effect of hyaluronidase addition to retrobulbar local anesthesia for phacoemulsification on intraocular pressure

Purpose The aim of this study was to evaluate the effect of adding hyaluronidase to local anesthetic agents on intraocular pressure (IOP) following retrobulbar anesthesia for patients scheduled for routine phacoemulsification.Patients and methods This is a prospective comparative study that included patients scheduled for routine phacoemulsification. Patients were classified into two groups: group A patients were planned to have retrobulbar blocks with lidocaine 2% and hyaluronidase 20 IU/ml, and group B patients were planned to have retrobulbar blocks with lidocaine 2% only without hyaluronidase. IOP was measured immediately before and 2, 5, and 10 min after retrobulbar anesthesia administration in both groups using a calibrated Tono-pen.Results The study included 60 eyes of 50 patients. The mean preinjection IOP in group A patients (hyaluronidase group) was 16.38±2.41 mmHg, whereas the mean 10-min postinjection IOP was 18.17±3.54 mmHg (P>0.05). The mean preinjection IOP in group B patients (nonhyaluronidase group) was 15.41±2.63 mmHg, whereas the mean 10-min postinjection IOP was 24.34±5.25 mmHg (P<0.001). The mean change in IOP in group A before and after retrobulbar anesthesia (IOP rise) was 1.79±2.96 mmHg, whereas in group B, the mean IOP rise was 8.93±4.74 mmHg (P<0.001).Conclusion Although the addition of hyaluronidase to lidocaine 2% before cataract surgery had no IOP-lowering effect, it also did not cause any significant rise of postinjection IOP and did keep it within the range of the preinjection IOP.

Influence of vitreal reflux on intraocular pressure after intravitreal application of bevacizumab

Background/Aim: Intravitreal drug injection cause an increase in intraocular pressure (IOP). The increase in IOP is directly proportional to the volume of drug injected into the eye and inversely to the vitreal reflux. The mixture of fluid, presents as a subconjunctival bleb, composed of vitreous and injected drug is called vitreal reflux. In this study changes in IOP after intravitreal injection of bevacizumab in relation to the vitreous regurgitation were observed. Methods: This prospective study involved 50 patients (57 injections). Bevacizumab was administered intravitreally at a dose of 1.25 mg/0.05 mL. According to the type of disease, patients with diabetic macular oedema, proliferative diabetic retinopathy, age-related macular degeneration, retinal vein occlusion, choroidal neovascularisation and central serous chorioretinopathy were included. They were divided into two groups - the first one without vitreal reflux and the second one with vitreal reflux. IOP values were measured at baseline, right after drug application and 20 min thereafter. Results: The reference value range of IOP values were 10-21 mmHg and so were the average baseline values in both experimental groups of patients (15.81 ± 3.50 mmHg). In the experimental group without reflux post application mean values of IOP at 0 and 20 min were 50 ± 9.65 and 18.54 ± 5.06 mmHg, respectively. In the experimental group with reflux post application mean IOP values after 0 and 20 min were 36 ± 8.68 mmHg and 18.91 ± 4.82 mmHg, respectively. Conclusions: Following intravitreal bevacizumab application, a significant increase in IOP occurs. After 20 minutes the IOP values spontaneously decreased below 25 mmHg in both groups and there was no significant difference in comparison with the baseline values. Vitreus reflux is a major factor in short-term post-injection IOP elevation, but not from the longer-term perspective.

EFFECT OF SERIAL ANTERIOR CHAMBER PARACENTESIS ON SUSTAINED INTRAOCULAR PRESSURE ELEVATION IN PATIENTS RECEIVING INTRAVITREAL ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR THERAPY.

To investigate the effect of serial anterior chamber (AC) paracenteses in eyes with sustained elevations of intraocular pressure (IOP) in the setting of repeated intravitreal injections (IVI) of anti-vascular endothelial growth factor medications. This is a retrospective records review of patients undergoing IVI of anti-vascular endothelial growth factor medication (bevacizumab, ranubizumab, or aflibercept), who demonstrated a sustained elevation of preinjection IOP and also received AC paracentesis immediately after IVI on at least three consecutive visits. Changes in preinjection IOP and cup-to-disk (C:D) ratio were compared before and after the initiation of IVI and before and after the introduction of AC paracenteses with each subsequent IVI. Twenty-three eyes of 17 patients receiving a median of 26 IVI experienced a rise in preinjection IOP from 16.3 mmHg to 21.1 mmHg (P = 0.004) and an increase in mean C:D ratio from 0.37 to 0.47 (P = 0.0002). After introduction of AC paracenteses (median of 12), mean IOP was returned to baseline 16.00 mmHg (P = 0.002), mean C:D ratio stabilized (0.50, P = 0.197), and maximum IOP decreased from 26.8 mmHg to 23.0 mmHg (P = 0.05). Nineteen (82.6%) eyes required an increase in topical glaucoma medications during the study period, and 13 (56.5%) still required additional therapies after initiation of AC paracenteses. Five eyes (38.5%) required laser or glaucoma drainage device procedures. Serial AC paracenteses reduced immediate postinjection IOP, and along with standard glaucoma care in most patients, reversed preinjection IOP elevation, and stabilized optic nerve changes associated with repeated intravitreal anti-vascular endothelial growth factor injections in a subset of patients with sustained elevation of preinjection IOP.

Effect of prior glaucoma surgery on intraocular pressure immediately after anti-vascular endothelial growth factor injection.

To characterize how prior incisional glaucoma surgery affects the intraocular pressure (IOP) elevation immediately following intravitreal anti-VEGF injections (IVI). Single institution, experimental study. Patients with a history of incisional glaucoma surgery who were receiving anti-VEGF injections were recruited as well as control eyes. Pre- and post-injection IOP measurements were compared as well as time to recovery to within 5 and 10mmHg of baseline IOP. Ten eyes with a history of glaucoma surgery and 29 control eyes receiving anti-VEGF injections were included. The most common indication for intravitreal anti-VEGF injection was proliferative diabetic retinopathy in both surgical and control eyes (50% vs 45%, p = 1.00). Post-injection IOP was significantly decreased compared to baseline IOP after anti-VEGF injection in surgical versus control eyes (26.5 ± 8.9mmHg vs 44.2 ± 8.5mmHg, respectively, p < 0.001). The mean change in IOP following intravitreal anti-VEGF injection was lower in surgical eyes (10.7 ± 6.6mmHg vs 28.6 ± 8.3mmHg, p < 0.001). The mean time for the IOP to return to within 10mmHg of pre-injection IOP was less in surgical eyes (5.2 ± 4.1min vs 13.3 ± 7.6min, p = 0.002). Eyes with prior incisional glaucoma surgery demonstrated a significantly lower post-injection IOP elevation and a faster recovery to within 10mmHg of their pre-injection IOP. Incisional glaucoma surgery may be considered for patients where the attenuation of post-injection IOP elevation is needed and other less invasive measures have failed.

Major factors affecting intraocular pressure spike after intravitreal ranibizumab injection: Vitreous reflux and its amount.

The aim of this study was to assess the effect of vitreous reflux and its amount on short-term intraocular pressure after intravitreal injection of ranibizumab. The study included 316 eyes of 276 patients. Intraocular pressures were measured before intravitreal injection (preIOP), immediately after intravitreal injection (postIOP0), and 30 min after intravitreal injection (postIOP30). The amount of vitreous reflux was evaluated by measuring conjunctival bleb diameter, and patients were grouped as; group 1: no vitreous reflux, group 2: less vitreous reflux, and group 3: more vitreous reflux. The data were analyzed using variance analysis, chi-square test, and regression analysis. PostIOP0 values were highest in group 1, followed by group 2 and group 3 (all p values < 0.001). PostIOP30 values were similar in group 1 and group 2 (p = 0.261), but were lower in group 3 than other two groups (p < 0.001, p = 0.001, respectively). Vitreous reflux was identified as the only factor affecting postinjection intraocular pressure changes (p < 0.001), and a negative correlation was found between the total number of intravitreal injection and vitreous reflux (p = 0.032). The major factor affecting short-term postinjection intraocular pressure elevation was vitreous reflux, and intraocular pressure levels increased as the amount of vitreous reflux decreased. Vitreous reflux and its amount decreased as the total number of intravitreal injection increased.

Optic Nerve Head Perfusion Before and After Intravitreal Antivascular Growth Factor Injections Using Optical Coherence Tomography-based Microangiography.

To use optical coherence tomography angiography (OCTA) to evaluate the changes in optic nerve head perfusion following intravitreal antivascular endothelial growth factor injections. Preinjection and postinjection intraocular pressure (IOP) and OCTA images were taken of both the injected and uninjected fellow eyes. Mean preinjection IOP was 16.6±4.7 mm Hg, which increased to a mean of 40.3±13.0 mm Hg (P<0.0001) during the first postinjection image and remained elevated at 36.1±11.5 mm Hg (P<0.0001) during the second postinjection image. Although no significant change was observed in flux, vessel area density, or normalized flux when comparing the OCTA preinjection and first postinjection images, a significant decrease at the second postinjection image was observed (P=0.03, 0.02, and 0.03, respectively). No significant change was observed in the uninjected fellow eye during the same time period (P=0.47, 0.37, and 0.38, respectively). Following an antivascular endothelial growth factor injection, mean IOP increased significantly and OCTA imaging of the optic nerve demonstrated a mild but significant decrease in optic nerve head perfusion parameters. Clinicians performing these injections should be aware of these findings and monitor the status of the optic nerve in patients undergoing injections.

Hypotensive efficacy of topical brimonidine for intraocular pressure spikes following intravitreal injections of antivascular endothelial growth factor agents: a randomised crossover trial

PurposeTo determine the effect of topical brimonidine tartrate prophylaxis on intraocular pressure (IOP) spikes following intravitreal injection of antivascular endothelial growth factor (anti-VEGF) agents.MethodsThis is a randomised crossover trial of...

Intraocular pressure change after injection of intravitreal dexamethasone (Ozurdex) implant in Korean patients

Background/AimsTo analyse intraocular pressure (IOP) changes over a period of 1 year after intravitreal dexamethasone (DEX, Ozurdex) implant injection and to compare the results with those of previously published studies...

Cluster endophthalmitis due to Stenotrophomonas maltophilia following intravitreal bevacizumab: outcomes of patients from North India

PurposeTo study features, management and outcomes of cluster endophthalmitis following intravitreal bevacizumab (BCZ) injection in North India.MethodsIn this retrospective study, 28 patients (23 men) (mean age of 59.07±13 years) who...

SAFETY OF INTRAVITREAL DEXAMETHASONE IMPLANT (OZURDEX): The SAFODEX study. Incidence and Risk Factors of Ocular Hypertension.

To analyze the incidence, risk factors, and time course of intraocular pressure elevation after intravitreal dexamethasone implant (Ozurdex). The medical charts of 421 consecutive eyes (361 patients) receiving one or more Ozurdex implant between October 2010 and February 2015 were reviewed retrospectively. Ocular hypertension was defined as intraocular pressure of at least 25 mmHg or an increase of at least 10 mmHg from baseline. The main indications for treatment were retinal vein occlusion (34%), diabetic macular edema (30%), postsurgical macular edema (17%), uveitis (14%), and other etiologies (5%). Among 1,000 intravitreal injections, ocular hypertension was recorded for 28.5% of injected eyes over a mean follow-up period of 16.8 months (3-55). Intraocular pressure-lowering medication was required for 31% of eyes. Only three eyes with preexisting glaucoma required filtering surgery to manage postinjection intraocular pressure elevation. Early retreatment between the third and fourth month does not increase the risk of intraocular pressure elevation. Younger age, male sex, Type 1 diabetes, preexisting glaucoma treated with dual or triple therapy, and a history of retinal vein occlusion or uveitis were significant risk factors for ocular hypertension after dexamethasone implant injection (P < 0.05 for all the above). Episodes of ocular hypertension after Ozurdex implant were generally transient and successfully managed with topical treatment. An analysis of the risk factors may help to determine the risk-benefit ratio for individual patients treated with dexamethasone implants.

Real-time measurement of needle forces and acute pressure changes during intravitreal injections.

The purpose of this study was to use a physiological pressure transducer to measure real-time, continuous pressure changes in an ex vivo study model of porcine eyes to record the amount of force needed for scleral penetration and to measure acute intraocular pressure rise during intravitreal injections. A pressure transducer was inserted into the anterior chamber of 30 fresh porcine eyes, and intraocular pressure was measured 2s prior to intravitreal injection until 2s after. A force transducer plate was used to insert various gauge needles into the vitreous cavity and the amount of force in Newtons (N) required for scleral penetration was recorded. For scleral perforation, 32- and 30-gauge needles required 0.44N and 0.45N, significantly less than larger gauge needles (P<0.05). Similarly, 27- and 25-gauge needles required more force than smaller gauge needles but less than 19 gauge (P<0.05). Intraocular pressure increased an average of 64.5mmHg during intravitreal injection. Two seconds postinjection intraocular pressure readings showed a residual intraocular pressure increase of 11.1mmHg from pre-injection baseline. Real-time continuous recordings of pressure reveal that an instantaneous intraocular pressure spike occurs during intravitreal injection and appears to be separate from the intraocular pressure spike that occurs during needle insertion. This pressure spike is transient and has not been captured by previous methods of intraocular pressure measurement, which rely on single time point measurements. The clinical significance of this brief intraocular pressure spike is unclear and warrants further investigation.