Prior Intravitreal Injections Research Articles

Bilateral vitrectomy in patients with proliferative diabetic retinopathy-characteristics and surgical outcomes.

Comparing characteristics and outcomes of patients with bilateral proliferative diabetic retinopathy (PDR) undergoing concurrent and sequential vitrectomy. Patients having bilateral vitrectomy were classified into concurrent (requiring bilateral surgery simultaneously) and sequential (indicating vitrectomy in one eye later) groups. Clinical characteristics and outcomes were compared, and correlation between the first and second-operated eyes was analyzed. One hundred eight and 126 eyes were in the concurrent and sequential groups, respectively. The sequential group was older (50 vs. 45years, P = 0.017), had less retinal detachment (54 vs. 77%, P < 0.001), and better visual outcomes (0.79 vs. 1.30,P = 0.021), especially the second-operated eyes. The concurrent group had weaker correlations of disease severity (phi coefficient: 0.36 vs. 0.61) and post-operative visual acuity (r: 0.12 vs. 0.34) between the first- and second-operated eyes than the sequential group. Prior intravitreal injection of anti-vascular endothelial growth factor (odds ratio [OR] 0.37, 95% confidence interval [CI] 0.15-0.86, P = 0.025) predicted better outcomes, while post-operative neovascular glaucoma predicted worse outcomes (OR 6.5, 95%CI 1.7-27.9, P = 0.008). PDR patients requiring surgery concurrently were younger and had more severe diseases and worse outcomes. However, poor outcomes in the first eye did not predict similar outcomes in the second eye.

Diabetes, Diabetic Retinopathy, and Intravitreal Injection as a Risk Factor of Posterior Capsular Rupture in Phacoemulsification Cataract Surgery :A Systematic Review and Meta Analysis

Abstract&#x0D; Introduction &amp; Objectives : The risk of PCR in patients with diabetes and its sequential complication including diabetic retinopathy and Intravitreal Injection (IVI) was still under debate. This study was aimed to summarize the risk of diabetes, diabetic retinopathy, and intravitreal injection towards PCR events during phacoemulsification cataract surgery.&#x0D; Methods : A systematic literature search was performed up to March 2023 from the last 10 years publications using Medline and Cochrane library databases. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) of diabetes, diabetic retinopathy, and IVI with PCR events were calculated using random-effects models. The quality of included studies was appraised using the Newcastle-Ottawa Scale.&#x0D; Results : Six studies about diabetes, six studies about diabetic retinopathy and seven studies about IVI were included in this meta-analysis. The pooled odds ratios of PCR in eyes with diabetes was 1.22 (95% CI: 1.16-1.28) I2 =0.0%, with the diabetic retinopathy patients was 1.23 (95% CI: 1.13-1.33) I2 =64.3%, and with prior IVI was 1.05 (95% CI: 1.03-1.08) I2 =51%.&#x0D; Conclusion : This meta-analysis emphasize that diabetes, diabetic retinopathy, and previous IVI significantly increase the risk of PCR on future phacoemulsification surgery. Further studies are needed to elucidate the underlying mechanism.

Intravitreal Injection Is Associated with Increased Posterior Capsule Rupture Risk during Cataract Surgery: A Meta-Analysis

Background: Although observational studies have suggested that prior intravitreal therapy may predict posterior capsule rupture (PCR) during cataract surgery, this finding is still controversial. Objective: This study aimed to summarize current evidence on the association between prior intravitreal injection (IVI) and PCR during cataract surgery. Methods: A systematic literature search was performed up to October 27, 2021. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using random-effects models. The potential association between IVI and PCR in future cataract surgeries was assessed using the following two models: “pooling the ORs of PCR in eyes with and without previous IVI(s)” and “pooling the ORs for PCR relative to each increase in the number of prior injections.” The quality of included studies was appraised using the Newcastle-Ottawa Scale. Results: Six cohort studies were included in this meta-analysis, with a total of 1,051,097 eyes that underwent cataract surgery. Of these, 7,034 eyes were associated with previous IVI. The pooled odds of PCR in eyes with prior IVI was 2.01 (95% CI: 1.35–3.00) times higher than that of eyes without an IVI history. An increase in the number of previous IVI conferred increased odds of PCR of 1.03 (95% CI: 1.01–1.06). After excluding studies that failed to account for confounders, the significantly increased risk was not altered, and the significant heterogeneity was minimized in both models. Conclusion: This meta-analysis provides evidence that previous IVI significantly increases the risk of PCR during future cataract surgery. The risk of PCR should be discussed preoperatively with patients. Further studies are required to validate our findings and explore the underlying mechanisms.

Prior pars plana vitrectomy and its association with adverse intraoperative events during cataract surgery.

To evaluate the risk of intraoperative complications during cataract surgery in eyes with a prior vitrectomy. A retrospective review of data from our cataract surgery registry of all patients undergoing cataract surgery between 2014 and 2018 at the University of Colorado Hospital. Univariate and multivariate analyses were conducted, accounting for intra-patient correlation in subjects who underwent two cataract surgeries. The three main outcomes of interest, zonulopathy, posterior capsule (PC) tears and dropped lens fragments, were analysed for their association with prior pars plana vitrectomy (PPV) and clinical characteristics of patients such as history of prior intravitreal injection and surgeon level of experience. 10 540 eyes of 6447 patients were included in the analysis. 371 (3.5%) eyes had a prior PPV. Eyes with a prior PPV experienced more zonulopathy during cataract surgery (adjusted OR 2.2, 95% confidence interval: 1.3-3.7, p = 0.002). Combined phacoemulsification/PPV were significantly more likely to experience all 3 complications, and this effect was even greater for eyes with a prior PPV. All complications were rare; however, there was a significant association with prior PPV and intraoperative zonulopathy. Cataract surgeons must be aware of a patient's prior vitrectomy and plan accordingly for the increased risk of intraoperative complications.

Prospective Study of Silicone Oil Microdroplets in Eyes Receiving Intravitreal Anti-Vascular Endothelial Growth Factor Therapy in 3 Different Syringes

To compare the prevalence of intravitreal silicone oil microdroplets detected by slit-lamp biomicroscopy in eyes with 6 or more injections of the same anti-vascular endothelial growth factor (VEGF) drug. Prospective, cross-sectional case series. A total of 260 consecutive eyes receiving 1 of 3 intravitreal anti-VEGF drugs for choroidal neovascularization, diabetic macular edema, or venous occlusive disease. The control group included 147 fellow eyes with no prior intravitreal injections. The anterior and mid-vitreous were carefully examined using 12× to 16× magnification through dilated pupils with ocular saccades before an injection. Silicone oil microdroplets were graded on a scale from 0 to 4+ based on the number and size of droplets. Presence and severity of silicone oil microdroplets in the vitreous. Silicone oil microdroplets were observed in 78.3% of eyes receiving bevacizumab in Becton Dickinson (BD, Franklin Lakes, NJ) 0.3-mL polypropylene syringes, 14.4% of eyes receiving ranibizumab in 1.0-mL BD polypropylene syringes or more recently glass prefilled syringes, 48.5% of eyes receiving aflibercept in 1.0-mL BD polycarbonate syringes, and 0% of eyes in controls. The differences among the 4 groups were statistically significant at P < 0.001. The severity of silicone oil microdroplets was significantly greater in eyes using BD 0.3-mL polypropylene syringes than BD 1.0-mL polypropylene syringes, BD 1.0-mL polycarbonate syringes, or controls (P < 0.001). The severity of silicone oil microdroplets in eyes using BD 1.0-mL polycarbonate syringes was significantly greater than BD 1.0-mL polypropylene syringes (P= 0.012) and controls (P < 0.001). There was no significant difference between silicone oil microdroplet severity between BD 1.0-mL polypropylene syringes and controls (P= 1.0). The BD 0.3-mL polypropylene syringes with repackaged bevacizumab and the BD 1.0-mL polycarbonate syringes with aflibercept cause a higher likelihood of silicone oil microdroplets. Intravitreal injections in eyes receiving multiple regular anti-VEGF injections should be supplied in silicone-free syringes.

Rhegmatogenous Retinal Detachment after Intravitreal Injection

To describe the clinical features and outcomes in patients with rhegmatogenous retinal detachment (RRD) after intravitreal injection of pharmacologic agents. Retrospecitve case series. Patients diagnosed with rhegmatogenous retinal detachment within 3 months of receiving an intravitreal injection of a pharmacologic agent for treatment of macular disease. Retrospective case series of reported cases of RRD in patients with prior intravitreal injection who underwent subsequent surgical repair at a university referral center. Visual acuity (VA), single surgery anatomic success rate (SSAS) and retinal reattachment at last follow-up. Thirteen patients were identified to have RRD within 3 months of intravitreal injection. Injection was performed in the inferotemporal quadrant in 12 of 13 eyes (92%) with a 31- or 32-gauge needle. Additional risk factors for RRD other than intravitreal injection were present in 5 of 13 eyes (38%), including prior pars plana vitrectomy (3 eyes), history of retinal tear (1 eye), and history of RRD in the fellow eye (1 eye). Average duration from time of injection to diagnosis of RRD was 27 days (range, 5-43 days). Retinal reattachment was achieved in 12 of 13 eyes (92%). Visual acuity returned to baseline in only 3 of 13 eyes (23%) at the last follow-up visit. Although RRD after intravitreal injection is rare, prior retinal surgery and alternate risk factors for RRD may predispose to RRD after intravitreal injection. Surgical outcomes were generally favorable, but VA outcomes were limited by the high rate of macula-off RRD and the underlying macular disease.

Association of Disorganization of Retinal Inner Layers With Visual Acuity Response to Anti–Vascular Endothelial Growth Factor Therapy for Macular Edema Secondary to Retinal Vein Occlusion

Disorganization of retinal inner layers (DRIL) has demonstrated significant correlations with visual acuity (VA) in center-involved diabetic macular edema. In patients with retinal vein occlusion (RVO) and secondary macular edema, DRIL may be a useful biomarker in determining VA outcomes. To examine whether DRIL at baseline and after treatment is associated with VA in RVO. A retrospective review of records of 147 patients 18 years or older with treatment-naive branch RVO (BRVO), central RVO (CRVO), or hemispheric RVO (HRVO), with a minimum of 12 months of follow-up, who presented to a tertiary ophthalmic center from December 1, 2010, to January 1, 2016, was conducted. Data collection continued through January 2017. Exclusion criteria included active confounding retinal or ocular disease, history of pars plana vitrectomy, or prior intravitreal injections. Two masked graders calculated a DRIL score based on DRIL presence in 3 predefined regions on spectral-domain optical coherence tomography at baseline, 6 months, and 12 months. A third masked grader was used for discrepancies. Anti-vascular endothelial growth factor (AVF) therapy (ranibizumab, aflibercept, or bevacizumab) determined by the treating physician. The DRIL score at baseline for determining VA outcomes and correlation of VA with changes in DRIL burden in response to AVF therapy. In the 147 patients (mean [SD] age, 68.9 [13.1] years; 75 [51.0%] female), baseline DRIL was seen in 91 eyes (61.9%). In the BRVO group but not the CRVO group, baseline DRIL was associated with lower baseline Early Treatment Diabetic Retinopathy Study (ETDRS) score (score of 66.7 for no DRIL vs 54.6 for DRIL, P = .002). Absence of DRIL at baseline in the CRVO/HRVO group correlated with greater VA gains at 6 months, adjusting for baseline VA (score change of 19.50 for no DRIL vs 12.72 for DRIL; P = .04). During 12 months, continued DRIL presence in BRVO was associated with less VA gain up to 6 months (score change of 6.2 for the DRIL increase group vs 18.6 for the DRIL decrease group vs 2.9 for the DRIL stable group; P = .02). Increasing DRIL scores in CRVO/HRVO were associated with reduced VA improvement at 6 months (score change of -0.12 for the DRIL increase group vs 16.90 for the DRIL decrease group vs 8.45 for the DRIL stable group; P = .002) and 12 months (score change of -1.91 for the DRIL increase group vs 17.83 for the DRIL decrease group vs 6.97 for the DRIL stable group; P < .001). Baseline DRIL presence and DRIL burden changes with AVF therapy for macular edema secondary to RVO may be useful biomarkers of ETDRS score improvements.

Risk of Posterior Capsule Rupture During Cataract Surgery in Eyes With Previous Intravitreal Injections

To investigate the risk of posterior capsular rupture (PCR) during cataract surgery in eyes with previous intravitreal injection (IVI). Retrospective cohort study. The Moorfields Patient Administrative System and OpenEyes electronic databases were used to study all cataract surgery procedures undertaken between January 1, 2012 and August 31, 2015 in the Moorfields main and satellite sites. Clinical data were anonymized and extracted, including prior occurrence and number of intravitreal injections. Logistic regression was performed with the Hosmer-Lemeshow test for goodness of fit to generate odds ratios for possible risk factors. In total, 62 994 cataract surgery procedures were undertaken over the study period, of which 1035 (1.64%) were in eyes with previous intravitreal injection(s). PCR occurred in 650 (1.04%) eyes. After logistic regression, prior intravitreal injection was associated with an increased risk of PCR (P= .037), with an odds ratio of 1.66. The number of prior injections, indication for injections, and service undertaking the surgery were not associated with increased risk of PCR (P > .1). Eyes with previous IVI have a higher risk of PCR. This is not affected by number of previous injections, indication for injections, or the specialty undertaking the surgery.

Impact of initial visual acuity on anti-VEGF treatment outcomes in patients with macular oedema secondary to retinal vein occlusions in routine clinical practice

AimTo determine the impact of initial visual acuity (VA) on anti-vascular endothelial growth factor (VEGF) treatment outcomes in patients with macular oedema secondary to retinal vein occlusions in routine clinical...

Rate of intraoperative complications during cataract surgery following intravitreal injections.

PurposeTo investigate the effect of prior intravitreal injections on intraoperative and postoperative complication rates associated with cataract surgery.MethodsA retrospective cohort analysis reviewed 10 105 cataract surgery procedures performed by experienced surgeons at the Duke Eye Center from 1 January 2005 to 10 December 2012. A group of 197 eyes with prior intravitreal injections was compared with an equal number of matched control eyes without prior injection using the Fisher's exact test of difference in proportions and the Wilcoxon rank-sum test of difference in means. Outcomes analyzed included baseline demographic information, preoperative clinical characteristics, prevalence of intraoperative complications, and postoperative intraocular pressure, glaucoma surgery, and glaucoma medication requirement through 1 year following cataract surgery.ResultsAn increased rate of intraoperative complications was identified during cataract surgery in eyes with prior intravitreal injections compared with control eyes (3 vs 0%, P=0.030). Injection eyes required more glaucoma medications at 1 year, but no difference was identified if steroid injections were excluded. No difference in postoperative IOP or glaucoma surgery was identified. No cases of endophthalmitis were reported.ConclusionsA history of intravitreal injections may be a risk factor for cataract surgery-related intraoperative complications. We hypothesize this may be due to unidentified iatrogenic lens trauma during intravitreal injections. Particular attention to the posterior capsule during preoperative assessment and intraoperatively is recommended in eyes undergoing cataract surgery with a prior history of intravitreal injections.

Previous Intravitreal Therapy Is Associated with Increased Risk of Posterior Capsule Rupture during Cataract Surgery

To investigate if previous intravitreal therapy is a predictor of posterior capsule rupture (PCR) during cataract surgery. Multicenter, national electronic medical record (EMR) database study with univariate and multivariate regression modeling. A total of 65 836 eyes of 44 635 patients undergoing cataract surgery. Anonymized data were extracted for eyes undergoing cataract surgery from 20 hospitals using the same EMR for cases performed between 2004 and 2014. Variables included as possible risk indicators for PCR were age, sex, number of previous intravitreal injections, indication for intravitreal therapy, grade of healthcare professional administering intravitreal therapy, advanced cataract, and cataract surgeon grade. Presence or absence of posterior capsular rupture during cataract surgery. Data were available on 65 836 cataract operations, of which 1935 had undergone previous intravitreal therapy (2.9%). In univariate regression analyses, patient age, advanced cataract, junior cataract surgeon grade, and number of previous intravitreal injections were significant predictors of PCR. By considering the number of previous intravitreal injections as a continuous variable, the odds ratio for PCR per intravitreal injection was 1.04 (P= 0.016) after adjusting for age, advanced cataract, and cataract surgeon grade. Repeat analysis considering intravitreal injections as a categoric variable showed 10 or more previous injections were associated with a 2.59 times higher likelihood of PCR (P= 0.003) after again adjusting for other significant independent predictors. Previous intravitreal therapy is associated with a higher likelihood of PCR during cataract surgery. This study provides data to help inform surgeons and patients about the risk of complications when undergoing cataract surgery after multiple prior intravitreal injections. Further investigation is required to determine the cause behind the increased PCR risk.

The role of preventive topical antibiotic treatment prior to intravitreal injection

Treatment of wet age-related macular degeneration (AMD) requires frequent intravitreal injections of anti-VEGF agents, sometimes on monthly basis during a long period of time. Endophthalmitis is a rare but extremely severe complication of intravitreal injections. As it has been proven before, the flora from the conjunctival surface is the main source for endophthalmitis. Using Povidone-iodine solution (Betadine10 % Povidone-iodine, EGIS PHARMACEUTICALS) is the only way to prevent endophthalmitis. The efficacy of it was proven by numerous studies. No evidence exists that topical antibiotiotics prior and after injections could be effective for prevention of endophthalmitis. Purpose: To study the advisability of topical antibiotic application before intravitreal injection. Materials and methods: Under investigation, there were 25 eyes of 25 patients with wet AMD treated by anti-VEGF intravitreal injections. All patients used topical antibiotics 3 days before injection. Conjunctival culture from injection eye was collected three times: before topical antibiotic use; after topical antibiotic use, and after Betadine 5 % application. Results: The rates of Staphylococcus epidermidis before and after topical antibiotic use were approximately equal. However there was no Staphylococcus epidermidis found after Betadine 5 % application. Conclusion: Our study showed the effectiveness of Betadine 5 % solution in conjunctival flora reduction. Use of topical antibiotics 3 days prior intravitreal injections is not effective. Key words: age-related macular degeneration; endophthalmitis; intravitreal injection; topical antibiotics; endophthalmitis prevention.

Evaluation of the dual staining technique for complete removal of idiopathic epimacular membranes

Purpose This study tries to evaluate the usefulness of the dual staining first with Triamcinolone acetonide (TA) to effectively visualize and remove the fibrous component of idiopathic epimacular membrane (EMM) and then with brilliant blue G (BBG) to selectively remove the internal limiting membrane (ILM). The primary outcome was the visual acuity improvement and the concomitant decrease in the central macular thickness (CMT) after surgery, and the secondary outcome was the condition of the ILM after this dual staining. Subjects and Methods A prospective, non-randomized, observational cohort study including 15 eyes .The inclusion criterion was a clinically detectable idiopathic EMM diagnosed by fundus examination or optical coherence tomography (OCT), causing a decrease of visual acuity. The exclusion criteria included prior intravitreal injection of TA or antivascular endothelial growth factor, ocular inflammation or prior trauma. During a standard 23 G vitrectomy, peeling the EMM was carried out after administration of TA, BBG (0.25 mg /mL) was injected onto the retinal surface utilizing the ''dry method'' or the ''air-filled technique''. Both stains will be completely washed out immediately. Then the surgeon recorded the characteristics of the underlying ILM before peeling. Postoperatively the patients were followed up at 1 day, 1 week, 1 month and at 6 months. Primary and secondary outcomes were recorded. Results Our patients included 8 (53.3%) females and 7 males (46.7%). A single surgeon performed all surgeries. TA was used to identify the posterior hyaloid in all 14 cases (93.3%) with no prior vitreous surgery and to effectively visualize and remove the idiopathic EMM in all 15 cases. Three (20%) of the cases had EMM remnants after BBG staining. When this dye was used to stain the ILM during surgery, the unstained EMM clearly stood out against the ILM, which was stained blue. After EMM peeling, all of the eyes had residual ILM except one (6.3%). In all eyes, the surgeon was unable to determine the status of the ILM before BBG staining. The ILM was present and damaged in 8 eyes (53.3%), while it was present and undamaged in 6 (40%). The mean preoperative CMT in eyes were the ILM was found to be damaged on table was 565.3 ± 79.9 μm, while the mean preoperative CMT in eyes were the ILM was undamaged was 446.6 ± 34.4 microns, this was statistically significant (P = 0.005). At 6 months, decimal BCVA improved from 0.18 ± 0.06 at baseline to 0.53 ± 0.11 (P = 0.005). Again at 6 months, the CMT also improved from 506.2 ± 90.03 ΅m at baseline to 365.8 ± 53.3 μm (P Conclusions In conclusion, dual staining starting with TA effectively led to adequate visualization and removal of the posterior hyaloid as well as the fibrous component of the idiopathic EMM. The subsequent BBG administration in an air filled vitreous (the dry technique) helped selective removal of the ILM with no deleterious effects on the functional or the anatomical outcomes of the procedure as demonstrated by the significant improvement in both the BCVA and the CMT 6 months after surgery.

The effect of the duration of visual impairment on the final functional outcome after 23 G vitrectomy for idiopathic epimacular membrane

PurposeTo evaluate the effect of the duration of symptoms on the final visual acuity improvement in patients operated for idiopathic epiretinal membrane (EMM) by the 23-G pars plana vitrectomy technique.Participants and methodsA prospective cohort study including 12 eyes of 12 patients (six male and six female) operated for idiopathic EMM at a specialized vitreoretinal center between March 2012 and March 2013 was carried out. We included clinically detectable idiopathic EMM diagnosed by fundus examination or optical coherence tomography (OCT), causing a decrease in the visual acuity or metamorphopsia. Exclusion criteria included prior vitreous surgery, prior intravitreal injection of triamcinolone acetonide or antivascular endothelial growth factor, ocular inflammation, or prior trauma. Postoperatively, patients were followed up for best-corrected Snellen visual acuity (BCVA), a standard ophthalmological examination, including fundoscopy, and OCT, which was performed to assess the thickness and the morphology. The central macular thickness (CMT) was defined as the central 1 mm zone. The main outcome measures of the study were the CMT change and the visual acuity improvement in relation to the preoperative duration of symptoms, the preoperative CMT, and the preoperative BCVA.ResultsThe study included 12 patients (male patients 50%) with a mean ± SD of age equal to 61.25 ± 6.077 years. Phacoemulsification with intraocular lens implantation was performed for the four (33.3%) phakic patients, and 23 G vitrectomy for removal of the epimacular membrane was performed for all eyes (100%). The mean preoperative BCVA was 0.12, with a range from 0.08 to 0.25, whereas the postoperative visual acuity showed a statistically significant improvement. It ranged from 0.16 to 0.66, with a mean of 0.39 (decimal). The mean postoperative CMT was 354.6 ± 73.7 μm, which was significantly thinner than the preoperative CMT of 536.25 ± 131.129 μm (P = 0.001). The mean preoperative CMT ranged from 380 to 780 μm, whereas the postoperative CMT ranged from 280 to 492 μm. None of the patients required suturing of thesclerotomy site at the end of the initial surgery.The postoperative BCVA was significantly correlated with the duration of symptoms (P = 0.029), the preoperative CMT, and also the postoperative CMT.ConclusionThe shorter the duration of symptoms, the better the postoperative BCVA after surgery for an idiopathic EMM. Also, the lower the preoperative CMT measured by OCT, the better the final visual outcome. Finally, the lower the postoperative CMT reached after 9 months from vitrectomy, the better the visual acuity.

Changes in Antibiotic Resistance Patterns of Conjunctival Flora Due to Repeated Use of Topical Antibiotics after Intravitreal Injection

To determine the effect of repeated intermittent use of topical antibiotics after intravitreal injections on conjunctival bacterial flora and antibiotic resistance. Cross-sectional case-control study. A total of 80 eyes of 40 patients were enrolled (40 study eyes, 40 control eyes). Patients were enrolled with unilateral exudative age-related macular degeneration who had received at least 3 prior intravitreal injections with use of postinjection topical antibiotics. Patients had received an average of 7 (range, 3-13) intravitreal injections before enrollment. At the time of enrollment, the inferior fornix of the treated eye was swept with a culture swab before use of povidone iodine; the inferior fornix of the fellow eye was also cultured and served as a control. The culture and sensitivity data from the study and control eyes were analyzed. The rate of antibiotic resistance among the conjunctival bacterial flora of the study eyes and control eyes. A total of 80 eyes of 40 patients were enrolled in the study; 29 patients used trimethoprim/polymyxin B drops, and 11 patients used fluoroquinolone drops after each injection. A total of 58 bacterial colonies were isolated from 50 eyes. There were no significant differences in bacterial species or culture positivity rates between study and control eyes. Coagulase-negative staphylococcus accounted for 41 of the 58 bacterial colonies (71%). There was a 63.6% resistance rate to fluoroquinolones among study eyes compared with 32.1% among control eyes (P < 0.05). In the subset of 11 study eyes using fluoroquinolone drops for 4 days after injection, there was an 87.5% resistance rate compared with 25.0% in matched control eyes (P = 0.04). There was no significant difference in trimethoprim resistance rates between study and control eyes: Four of 14 study eyes (28.6%) showed resistance compared with 5 of 18 control eyes (27.7%) (P = 1.0). Use of fluoroquinolone drops after intravitreal injection leads to increased rates of resistance among conjunctival flora. Repeated use of topical fluoroquinolones after intravitreal injections may have a detrimental effect on eye health by breeding resistance in the bacterial flora.

A Prospective Study of Early Intraocular Pressure Changes After a Single Intravitreal Triamcinolone Injection

To prospectively monitor intraocular pressure (IOP) and gonioscopy changes within the first month after a single 4-mg intravitreal injection of triamcinolone acetonide (IVK) (Kenalog, Briston-Meyers Squibb, New York). Prospective comparative interventional case series. A consecutive series of 28 eyes of 14 patients with no prior intravitreal injections or history of glaucoma were prospectively enrolled. After baseline evaluation in both eyes, including IOP, gonioscopy, and optic nerve evaluation, a single 4-mg IVK was given in a standard sterile fashion in the eye to be treated. Eyes received IVK for macular edema associated with retinal vein occlusions and in conjunction with photodynamic therapy for choroidal neovascularization secondary to age-related macular degeneration, ocular histoplasmosis, and high myopia. The fellow eye served as the control. After the injection, IOP and gonioscopy were repeated at 1, 2, and 4-week intervals in both eyes. Of the 14 patients, the 5 women and 9 men had a mean age of 67.6 years. Mean baseline IOP of the treated and fellow control eyes were similar at 15.9 versus 16.6 mm Hg, respectively. The control eyes maintained a small IOP range (15.6 to 16.6 mm Hg) during the 1-month follow-up period. In the treated eyes, the mean maximum IOP was 54% above baseline during follow-up, compared with 11% for control eyes. Six of 14 (43%) treated eyes had IOP elevation to 24 mm Hg or higher with mean change of 8.6 mm Hg and a mean maximum IOP of 32.1 mm Hg. There was no correlation between IOP rise and age, sex, diagnosis, or optic nerve appearance. However, during the course of the study, 4 of 6 (67%) of the treated eyes that required topical drops for the IOP elevation had documented abnormal inferior angle changes characterized by pigmented particulate matter in the inferior angle not present at the baseline exam. The most frequent time point for an IOP elevation that required treatment was at 2-week postinjection. No eyes required surgical management of IOP during the course of this 4-week study. We observed a significant IOP rise in eyes after a single intravitreal injection of 4 mg of triamcinolone within 1 month of injection. In this study, the most frequent time point that required IOP treatment was at 2-week postinjection, suggesting that early and frequent monitoring of IOP should be considered. Two-thirds of eyes that required medical control of IOP developed gonioscopy changes, characterized by particulate matter in the inferior angle, not present at baseline. Eyes that developed gonioscopic changes were 5 times more likely to be treated for IOP elevation than those without gonioscopic findings.

Optical Coherence Tomography Findings After an Intravitreal Injection of Bevacizumab (Avastin®) for Macular Edema From Central Retinal Vein Occlusion

To determine whether bevacizumab could improve visual acuity and optical coherence tomography outcomes in a patient with macular edema from central retinal vein occlusion, an intravitreal injection of bevacizumab (1.0 mg) was given. Prior intravitreal injections of triamcinolone acetonide resulted in vision improvement but worsening cataract and borderline glaucoma. Within 1 week of the bevacizumab injection, visual acuity improved from 20/200 to 20/50 and optical coherence tomography revealed resolution of the cystic maculopathy. The improvements were maintained for at least 4 weeks. Intravitreal injections of bevacizumab may provide another treatment option for patients with macular edema from vein occlusions.

Rabbit Ciliary Process Responses to Different Routes of Water-Soluble Marihuana-Derived Material Administration

AbstractThe pharmacologic and morphologic effects of water-soluble marihuana-derived material (MDM) were examined in rabbits after different routes of administration. Subcutaneous (SC) MDM alone caused little change in intraocular pressure (IOP) yet significantly antagonized subsequent intravenous (IV) or intravitreal (IVT) MDM injections; this occurred despite the failure of SC MDM alone to induce morphological changes in the ciliary processes. Morphologic effects are usually associated with a pharmacologic response. IV MDM alone induced a large IOP fall that accompanied substantial morphologic changes; further IV MDM was ineffective in causing a change in IOP until 4 or 5 days after the initial injection. IVT MDM after IV MDM caused a fall in IOP with additional morphologic effects. IVT MDM alone caused marked pharmacologic and morphologic changes, and IV MDM after IVT MDM caused additional morphologic changes that accompanied an IOP fall. IVT injections, after a prior IVT injection, were pharmacologica...

Somatostatin-like immunoreactive material in the rabbit retina

Somatostatin-like immunoreactivity was detected by a specific radioimmunoassay in extracts of retinas of Dutch-belted rabbits at a mean concentration of1.1±0.1 ng/retina, or 170±30 pg/mg protein. On both gel permeation chromatography and reversed phase high performance liquid chromatography, the majority of this material was indistinguishable from somatostatin-14; a smaller amount of immunoreactive material co-chromatographed with somatostatin-28. The somatostatin-like immunoreactivity was concentrated in a P 2 (synaptosomal) fraction prepared by differential centrifugation. The concentration of somatostatin-like immunoreactivity was unaffected by the prior intravitreal injection of the selective neurotoxins 6-hydroxydopamine and 5, 7-dihydroxytryptamine. The rabbit retina, therefore, contains readily detectable amounts of material chemically similar to somatostatin-14 and somatostatin-28. This material is concentrated in neurosecretory elements of the retina, but is not contained in cells which accumulate dopamine or indoleamines. The rabbit retina is suitable for in vitro studies of the central nervous system function of the somatostatin family of peptides.