Jason Hsu

The role of topical antibiotic prophylaxis to prevent endophthalmitis after intravitreal injection.

OBJECTIVE To compare the incidence of endophthalmitis after intravitreal injection with and without topical postinjection antibiotic prophylaxis. DESIGN Retrospective case-control study. PARTICIPANTS All patients treated with intravitreal injection of ranibizumab, bevacizumab, or aflibercept for a variety of retinal vascular diseases at a single, large retina practice between January 1, 2009, and October 1, 2012, were included. METHODS The total numbers of patients and injections were determined from a review of billing code and practice management records. Endophthalmitis cases were determined from billing records and from an infection log. All cases of endophthalmitis were confirmed with chart review. A 28-month period when topical antibiotics were prescribed after intravitreal injection was compared with a 9-month period when topical antibiotics were not prescribed. Patients treated during an 8-month transition period were excluded to allow for the conversion of antibiotic prescription practices. MAIN OUTCOME MEASURES Incidence of endophthalmitis, visual acuity outcomes, and microbial spectrum. RESULTS During the study period, a total of 117 171 intravitreal injections were performed (57 654 injections during the topical antibiotic period, 24 617 during the transition period, and 34 900 during the no-antibiotic period), with a total of 44 cases of suspected endophthalmitis (0.038%; 1 in 2663 injections), 17 of which showed culture-positive results (0.015%; 1 in 6892 injections). During the 28-month topical antibiotic period, there were 28 cases of suspected endophthalmitis (0.049%; 1 in 2059 injections), 10 of which showed culture-positive results (0.017%; 1 in 5765 injections). During the 9-month no-antibiotic period, there were 11 cases of suspected endophthalmitis (0.032%; 1 in 3173 injections), 4 of which showed culture-positive results (0.011%; 1 in 8725 injections). Topical antibiotic use was associated with a trend toward increased risk of suspected endophthalmitis (odds ratio [OR], 1.54; 95% confidence interval [CI], 0.77-3.10) and culture-positive endophthalmitis (OR, 1.51; 95% CI, 0.47-4.83). CONCLUSIONS The incidence of endophthalmitis after intravitreal injection is low. Using postinjection topical antibiotic drops does not reduce the risk of endophthalmitis developing and is associated with a trend toward higher incidence of endophthalmitis.

Intravitreal bevacizumab (avastin) in central retinal vein occlusion.

Purpose: To describe the effects of intravitreal bevacizumab in eyes with macular edema resulting from central retinal vein occlusions (CRVO). Methods: Retrospective consecutive case series of patients diagnosed with macular edema from CRVO who received intravitreal bevacizumab. Results: Thirty eyes of 29 patients with an average age of 72 years (range, 54–87 years) had intravitreal bevacizumab injections. Mean follow-up was 18.1 weeks. Initial mean visual acuity was 20/394. At the 1- and 2-month follow-up, mean visual acuity improved to 20/237 (n = 26, P = 0.04) and 20/187 (n = 21, P = 0.008), respectively. At the 3- and 4-month follow-up, visual acuity improved from 20/228 to 20/157 (n = 15, P = 0.05) and from 20/313 to 20/213 (n = 11, P = 0.03), respectively. No significant changes in visual acuity were found after 4 months though the number of patients in this group was small. Duration of treatment effect following an injection appears to be limited to 2 months for most patients. No ocular or systemic adverse reactions were noted. Conclusions: The visual benefits of intravitreal bevacizumab for macular edema due to CRVO are apparent early but are not sustained without repeated injections. Larger clinical studies with long-term follow-up will be necessary to better elicit the best regimen for this therapy.

Hypotony after 25-gauge vitrectomy using oblique versus direct cannula insertions in fluid-filled eyes.

Purpose: To compare intraocular pressure (IOP) and rates of postoperative hypotony with 25-gauge pars plana vitrectomy (PPV) without tamponade using oblique versus direct cannula insertions. Methods: A prospective consecutive series of eyes that underwent 25-gauge PPV without tamponade using an oblique cannula insertion technique was compared with a historical consecutive series of eyes that underwent 25-gauge PPV without tamponade using direct cannula insertions. IOP was recorded before surgery, on postoperative day 1, and on postoperative week 1. Results: Ninety-five eyes had 25-gauge PPV without tamponade, 55 with oblique cannula insertions and 40 with direct insertions. With oblique insertions, there was no statistically significant difference between mean IOPs measured before surgery, on postoperative day 1, and on postoperative week 1. Only 1 (1.8%) of the 55 eyes had hypotony (IOP, ≤5 mmHg) on postoperative day 1. With direct insertions, mean postoperative day 1 IOP was significantly lower than mean preoperative IOP (P = 0.009). Mean preoperative and postoperative week 1 IOPs were similar. Four (10%) of 40 eyes had hypotony on postoperative day 1. Conclusions: Oblique cannula insertions may be superior to direct cannula insertions for lowering rates of absolute and relative postoperative day 1 hypotony in 25-gauge PPV without tamponade.

Baseline Choroidal Thickness as a Predictor for Response to Anti–Vascular Endothelial Growth Factor Therapy in Diabetic Macular Edema

PURPOSE To determine the association between baseline subfoveal choroidal thickness and short-term response to intravitreal anti-vascular endothelial growth factor (anti-VEGF) therapy in diabetic macular edema (DME). DESIGN Retrospective, consecutive case series. METHODS Fifty-three eyes from 42 patients diagnosed with treatment-naïve DME were treated with 3 monthly intravitreal injections of ranibizumab or bevacizumab. Serial enhanced depth imaging optical coherence tomography scans were used to measure subfoveal choroidal thickness and central macular thickness (CMT). Anatomic response (CMT decrease ≥ 50 μm) and functional response (best-corrected visual acuity gain ≥ 1 line) were assessed at 3 months follow-up using univariate and multivariate analyses. RESULTS After 3 monthly anti-VEGF treatments, subfoveal choroidal thickness decreased significantly (225 μm at baseline, 201 μm at 3 months, P < .0001). The anatomic responder group (32 eyes) had a greater baseline choroidal thickness (243 ± 15 μm) than the nonresponder group (21 eyes, 198 ± 13 μm, P = .03). Similarly, the functional responder group (28 eyes) tended to have a greater baseline subfoveal choroidal thickness (239 ± 12 μm) than the nonresponder group (25 eyes, 211 ± 16 μm, P = .08). Multivariate analyses revealed that a greater baseline subfoveal choroidal thickness was associated with a better anatomic (odds ratio = 1.12 for every 10 μm increase, P = .03) and functional response (odds ratio = 8.45 for >200 μm vs ≤ 200 μm, P = .008). CONCLUSION Baseline subfoveal choroidal thickness may help predict which patients with DME will respond more favorably in the short term to intravitreal anti-VEGF pharmacotherapy. In this study, eyes with a thicker baseline subfoveal choroidal thickness had better short-term anatomic and functional responses.

Acute Visual Acuity Loss Following Intravitreal Bevacizumab for Diabetic Macular Edema

A 58-year-old woman with non-proliferative diabetic retinopathy presented with decreased visual acuity from chronic macular edema. She had undergone multiple treatments previously, including focal laser treatment and intravitreal triamcinolone acetonide. Within 2 days of treatment with intravitreal bevacizumab, the patient noted a significant decrease in visual acuity. Fluorescein angiogram demonstrated an enlargement of the foveal avascular zone and persistent late leakage following intravitreal bevacizumab; optical coherence tomography performed before and after treatment revealed persistent cystoid macular edema. The use of intravitreal bevacizumab in chronic, refractory diabetic macular edema may cause acute visual acuity loss by disrupting an already fragile vascular perfusion status, leading to macular ischemia.

Conjunctival Flora Antibiotic Resistance Patterns After Serial Intravitreal Injections Without Postinjection Topical Antibiotics

PURPOSE To report conjunctival bacterial flora antibiotic resistance patterns after serial intravitreal injections performed using a povidone-iodine preparation without the use of preinjection or postinjection topical antibiotics. DESIGN Prospective, interventional case series. METHODS SETTING Single-center clinical practice in Pennsylvania. STUDY POPULATION Thirteen eyes of 13 treatment-naïve patients undergoing serial intravitreal anti-vascular endothelial growth factor (VEGF) injections for exudative age-related macular degeneration or macular edema attributable to retinal vein occlusion. INTERVENTION Conjunctival cultures from the treatment eye were performed prior to each injection preparation. A minimum of 3 monthly conjunctival cultures were obtained per eye over the course of the study. Ocular surface preparation consisted of topical anesthetic and povidone-iodine 5% without the use of preinjection or postinjection topical antibiotics. MAIN OUTCOME MEASURES Conjunctival flora growth patterns and antibiotic resistance patterns to several common antibiotics tested over the course of the study. RESULTS A total of 48 cultures were performed with a 77% culture positivity rate. Over the course of the serial conjunctival cultures in each patient, there was no evidence for emergence of resistant bacteria to any of the tested antibiotics (including fluoroquinolones and azithromycin) or significant alteration from baseline conjunctival flora. Of the 47 bacterial isolates, the most commonly isolated organism was coagulase-negative Staphylococcus both at baseline (73%) and following serial intravitreal injections (78%, P = .73). CONCLUSIONS Ocular surface preparation for intravitreal injection using povidone-iodine 5% alone in the absence of postinjection topical antibiotics does not appear to promote bacterial resistance or a discernible change in conjunctival flora.

Management of Thick Submacular Hemorrhage With Subretinal Tissue Plasminogen Activator and Pneumatic Displacement for Age-Related Macular Degeneration

PURPOSE To evaluate the outcome of pars plana vitrectomy, subretinal tissue plasminogen activator (t-PA) infusion and intraocular gas tamponade with and without postsurgical antivascular endothelial growth factor (VEGF) injection for thick submacular hemorrhage due to exudative age-related macular degeneration (AMD). DESIGN Retrospective, comparative, interventional case series. METHODS setting: 2 retina referral centers. The patient population included 101 eyes of 101 patients with neovascular AMD and thick submacular hemorrhage who underwent surgical displacement of the hemorrhage with or without postoperative anti-VEGF injections. Main outcome measures included degree of blood displacement, best and final postoperative visual acuity (VA), and adverse events. Snellen acuity was converted to logMAR for statistical analysis. RESULTS All patients were followed for a minimum of 3 months (mean, 15.3 months, range, 3-70 months). In 83 (82%) of 101 eyes, the procedure resulted in complete hemorrhage displacement from the fovea. Mean preoperative VA was 20/2255 (2.05 logMAR). The acuity significantly improved to 20/893 (1.65 logMAR) at month 1 (P < 0.001) at month 1; 20/678 (1.53 logMAR) at month 3 (P < 0.001), and 20/1150 (1.76 logMAR) at month 12 (P = 0.002). Best postoperative visual acuity improved by at least 1 line in 83 (82%) of 101 eyes, and 19.6% of eyes gained 3 lines or more at month 3. The visual acuity of the group of eyes that received postoperative anti-VEGF injection (n = 39) showed greater visual acuity improvement 6 months postoperatively compared to the group of eyes that did not receive postoperative anti-VEGF. Postoperative complications included vitreous hemorrhage in 2 eyes, rhegmatogenous retinal detachment in 4 eyes, and recurrent thick subretinal hemorrhage in 6 eyes. CONCLUSIONS Vitrectomy with subretinal t-PA injection and gas tamponade was found to be relatively effective for displacement of thick submacular hemorrhage with a significant improvement in visual acuity. There is a loss of acuity over time; the addition of postoperative anti-VEGF therapy may help maintain the visual acuity gains.

Bimanual assisted eyelid retraction technique for intravitreal injections.

Purpose: To describe an alternative technique for avoiding contact with the lids and eyelashes without the use of a metal lid speculum along with the results in clinical practice. Methods: Retrospective review of the medical records of all patients undergoing intravitreal injections of bevacizumab and ranibizumab with lid retraction achieved by bimanual assisted eyelid retraction between November 2010 and December 2011. Results: A total of 10,164 consecutive intravitreal injections were performed, of which 3,834 were bevacizumab and 6,330 were ranibizumab. In this cohort of patients, 3 suspected cases of endophthalmitis developed (2 culture-negative), corresponding to a rate of 0.03%. Conclusion: The technique of bimanual assisted eyelid retraction for intravitreal injection has a low rate of infection similar to the reported rates using a metal lid speculum.

Oral Eplerenone for Treatment of Chronic Central Serous Chorioretinopathy: A Case Series

BACKGROUND AND OBJECTIVE To evaluate the effect of oral eplerenone on subretinal fluid, visual acuity, and choroidal thickness in patients with chronic central serous chorioretinopathy (CSCR). PATIENTS AND METHODS Retrospective review of all patients (14 eyes of 14 patients) monitored for a minimum of 3 months with chronic CSCR who were treated with oral eplerenone in a single multi-physician retina practice. Visual acuity, dilated funduscopic examination, and spectral-domain ocular coherence tomography (OCT) with enhanced depth imaging (EDI) were obtained at each visit. Measurement of subfoveal fluid (SFF) height and choroidal thickness were performed. Two-tailed paired t test was used to calculate statistical significance of pre- and post-treatment variables. RESULTS At 1 month, 10 of 14 eyes had decreased SFF height on OCT and two eyes had complete resolution of SFF. Mean SFF height decreased from 130 µm to 62 µm (P = .05). Mean choroidal thickness decreased from 315 µm to 282 µm (P = .07). Mean visual acuity improved from logMAR 0.41 to 0.40. At 3 months, 13 of 14 (93%) had decreased SFF on OCT, and nine eyes (64%) had complete resolution of SFF. Mean SFF height decreased to 21 µm (P = .004). Mean choroidal thickness decreased to 253 µm (P = .10). Mean visual acuity improved to logMAR 0.28 (P = .02). CONCLUSION Oral eplerenone may be effective in treating patients with chronic CSCR.

Advances in drug delivery to the posterior segment.

Purpose of review Emerging developments and research for drug delivery to the posterior segment offer a promising future for the treatment of vitreoretinal disease. As new technologies enter the market, clinicians should be aware of new indications and ongoing clinical trials. Recent findings This review summarizes the advantages and shortcomings of the most commonly used drug delivery methods, including vitreous dynamics, physician sustainability and patient preferences. Currently available, intravitreal, corticosteroid-release devices offer surgical and in-office management of retinal vascular disease and posterior uveitis. The suprachoroidal space offers a new anatomic location for the delivery of lower dose medications directly to the target tissue. Implantable drug reservoirs would potentially allow for less frequent intravitreal injections reducing treatment burdens and associated risks. Newer innovations in encapsulated cell technology offer promising results in early clinical trials. Summary Although pars plana intravitreal injection remains the mainstay of therapy for many vitreoretinal diseases, targeted delivery and implantable eluting devices are rapidly demonstrating safety and efficacy. These therapeutic modalities offer promising options for the vitreoretinal therapeutic landscape.