Development of a Patient-Reported Outcome Measure to Assess Symptoms Associated with Cataract Surgery and Intraocular Lens Implants.

PURPOSE: To develop a standardized patient-reported outcome measure of visual perceptions and symptoms for implanted premium and monofocal intraocular lenses (IOLs). DESIGN: Observational study before and after IOL implants to assess the measure and symptom experience. PARTICIPANTS: Adults scheduled for binocular implantation of the same IOL type completed the survey at baseline prior to surgery (n = 716) and postoperatively (n = 554). Most respondents were female (64%), White (81%), 61 or older (89%), and had some college or more education (62%). METHODS: Administration was by web survey with mail follow-up and phone reminders. MAIN OUTCOME MEASURES: Frequency, severity, and level of symptom bother in the last 7 days for 14 symptoms: (1) glare, (2) hazy vision, (3) blurry vision, (4) starbursts, (5) halos, (6) snowballs, (7) floaters, (8) double images, (9) rings and spider webs, (10) distortion, (11) light flashes with eyes closed, (12) light flashes with eyes open, (13) shimmering images, and (14) dark shadows. RESULTS: The median correlation among having 14 symptoms at baseline was only 0.19. Mean uncorrected binocular visual acuity improved from a preoperative value of 0.47 logarithm of the minimum angle of resolution (logMAR; Snellen 20/59) to a postoperative value of 0.12 (20/26) and best-corrected binocular visual acuity improved from 0.23 logMAR (20/34) preoperative to 0.05 logMAR (20/22) postoperative. The most bothersome symptoms were reduced after surgery: preoperative/postoperative glare (84%/36%), blurry vision (68%/22%), starbursts (66%/28%), hazy vision (63%/18%), snowballs (55%/17%), and halos (52%/22%). All symptoms decreased significantly (P < 0.0001) from before to after surgery except for dark crescent-shaped shadows (4%/4%). The percentage of symptoms rated as quite a bit or extremely bothersome declined from before to after surgery except for dark crescent-shaped shadows (29%/32%): blurry vision (54%/15%), snowballs (52%/14%), glare (49%/15%), and halos (46%/14%). Having monofocal IOL implants was associated with significantly more reduction in halos, starbursts, glare, and rings and spider webs, but less improvement in self-reported general vision. CONCLUSIONS: This study provides support for the 37-item Assessment of IntraOcular Lens Implant Symptoms (AIOLIS) instrument for use to assess symptoms and general perceptions of vision in clinical studies and clinical care. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

Symptoms and Satisfaction Levels Associated with Intraocular Lens Implants in the Monofocal and Premium IOL Patient-Reported Outcome Measure Study.

PURPOSE: To develop a questionnaire with standardized questions and images about visual symptoms and satisfaction administered before and after cataract surgery with monofocal and various (premium) intraocular lenses (IOLs). DESIGN: A prospective, observational study of cataract surgery patients completing a self-administered questionnaire preoperatively and postoperatively at 4 to 6 months. PARTICIPANTS: Five hundred fifty-four patients with plans to undergo implantation of the same IOL in both eyes on separate occasions in 20 ophthalmology practices. METHODS: An 86-item questionnaire with standardized images assessed the following 14 symptoms: glare, blurry vision, starbursts, hazy vision, snowballs, halos, floaters, double images, rings and spider webs, light flashes with eyes closed, distortion, light flashes with eyes open, shimmering images, and dark crescent-shaped shadows. MAIN OUTCOME MEASURES: Symptom severity and level of symptom bother, satisfaction with vision, quality of vision, and ability to see without corrective lenses or eyeglasses. RESULTS: Except for dark crescent-shaped shadows, the report of visual symptoms significantly decreased postoperatively. Best uncorrected binocular visual acuity improved from 0.47 (20/59 Snellen visual acuity values) ± 0.35 logarithm of the minimum angle of resolution (logMAR) preoperatively to 0.12 (20/26 Snellen visual acuity values) ± 0.12 logMAR postoperatively. Patients' ratings of intermediate vision as good to excellent improved significantly from 12% preoperatively to 71% postoperatively, and patients' ratings of distance vision improved from 8% preoperatively to 85% postoperatively. After surgery, 84% reported that they were somewhat, very, or completely satisfied with their vision. Most patients (88%) reported that they could see pretty well, very well, or perfectly well without corrective lenses after surgery. CONCLUSIONS: The Assessment of IntraOcular Lens Implant Symptoms questionnaire can be used across a wide variety of IOLs to evaluate visual symptoms and satisfaction with a growing segment of the market, premium IOLs, that target intermediate and near vision, in addition to distance vision. Compared to patients receiving monofocal IOLs, patients receiving premium IOLs appear to be more challenging to satisfy because of their requirements for distance, intermediate, and near vision, and their desire to be free of eyeglasses postoperatively. This instrument provides a structured, uniform tool for regulators, researchers, and ophthalmologists in everyday practice to gain insights into patients' experiences. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Shear-Thinning Viscous Materials for Subconjunctival Injection of Microparticles.

While drug-loaded microparticles (MPs) can serve as drug reservoirs for sustained drug release and therapeutic effects, needle clogging by MPs poses a challenge for ocular drug delivery via injection. Two polymers commonly used in ophthalmic procedures-hyaluronic acid (HA) and methylcellulose (MC)-have been tested for their applicability for ocular injections. HA and MC were physically blended with sunitinib malate (SUN)-loaded PLGA MPs for subconjunctival (SCT) injection into rat eyes. The HA and MC viscous solutions facilitated injection through fine-gauged needles due to their shear-thinning properties as shown by rheological characterizations. The diffusion barrier presented by HA and MC reduced burst drug release and extended overall release from MPs. The significant level of MP retention in the conjunctiva tissue post-operation confirmed the minimal leakage of MPs following injection. The safety of HA and MC for ocular applications was demonstrated histologically.

Controlled release of dexamethasone sodium phosphate with biodegradable nanoparticles for preventing experimental corneal neovascularization.

Corneal neovascularization (CNV) leads to the loss of corneal transparency and vision impairment, and can ultimately cause blindness. Topical corticosteroids are the first line treatment for suppressing CNV, but poor ocular bioavailability and rapid clearance of eye drops makes frequent administration necessary. Patient compliance with frequent eye drop application regimens is poor. We developed biodegradable nanoparticles (NP) loaded with dexamethasone sodium phosphate (DSP) using zinc ion bridging, DSP-Zn-NP, with dense coatings of poly(ethylene glycol) (PEG). DSP-Zn-NP were safe and capable of providing sustained delivery of DSP to the front of the eye following subconjunctival (SCT) administration in rats. We reported that a single SCT administration of DSP-Zn-NP prevented suture-induced CNV in rats for two weeks. In contrast, the eyes receiving SCT administration of either saline or DSP solution developed extensive CNV in less than 1 week. SCT administration of DSP-Zn-NP could be an effective strategy in preventing and treating CNV.

Autologous serum eye drops for dry eye.

BACKGROUND: Theoretically, autologous serum eye drops (AS) offer a potential advantage over traditional therapies on the assumption that AS not only serve as a lacrimal substitute to provide lubrication but contain other biochemical components that allow them to mimic natural tears more closely. Application of AS has gained popularity as second-line therapy for patients with dry eye. Published studies on this subject indicate that autologous serum could be an effective treatment for dry eye. OBJECTIVES: We conducted this review to evaluate the efficacy and safety of AS given alone or in combination with artificial tears as compared with artificial tears alone, saline, placebo, or no treatment for adults with dry eye. SEARCH METHODS: We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register) (2016, Issue 5), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to July 2016), Embase (January 1980 to July 2016), Latin American and Caribbean Literature on Health Sciences (LILACS) (January 1982 to July 2016), the ISRCTN registry (www.isrctn.com/editAdvancedSearch), ClinicalTrials.gov (www.clinicaltrials.gov) and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We also searched the Science Citation Index Expanded database (December 2016) and reference lists of included studies. We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 5 July 2016. SELECTION CRITERIA: We included randomized controlled trials (RCTs) that compared AS versus artificial tears for treatment of adults with dry eye. DATA COLLECTION AND ANALYSIS: Two review authors independently screened all titles and abstracts and assessed full-text reports of potentially eligible trials. Two review authors extracted data and assessed risk of bias and characteristics of included trials. We contacted investigators to ask for missing data. For both primary and secondary outcomes, we reported mean differences with corresponding 95% confidence intervals (CIs) for continuous outcomes. We did not perform meta-analysis owing to differences in outcome assessments across trials. MAIN RESULTS: We identified five eligible RCTs (92 participants) that compared AS versus artificial tears or saline in individuals with dry eye of various origins (Sjögren's syndrome-related dry eye, non-Sjögren's syndrome dry eye, and postoperative dry eye induced by laser-assisted in situ keratomileusis (LASIK)). We assessed the certainty of evidence as low or very low because of lack of reporting of quantitative data for most outcomes and unclear or high risk of bias among trials. We judged most risk of bias domains to have unclear risk in two trials owing to insufficient reporting of trial characteristics, and we considered one trial to have high risk of bias for most domains. We judged the remaining two trials to have low risk of bias; however, these trials used a cross-over design and did not report data in a way that could be used to compare outcomes between treatment groups appropriately. Incomplete outcome reporting and heterogeneity among outcomes and follow-up periods prevented inclusion of these trials in a summary meta-analysis.Three trials compared AS with artificial tears; however, only one trial reported quantitative data for analysis. Low-certainty evidence from one trial suggested that AS might provide some improvement in participant-reported symptoms compared with artificial tears after two weeks of treatment; the mean difference in mean change in symptom score measured on a visual analogue scale (range 0 to 100, with higher scores representing worse symptoms) was -12.0 (95% confidence interval (CI) -20.16 to -3.84; 20 participants). This same trial found mixed results with respect to ocular surface outcomes; the mean difference in mean change in scores between AS and artificial tears was -0.9 (95% CI -1.47 to -0.33; 20 participants; low-certainty evidence) for fluorescein staining and -2.2 (95% CI -2.73 to -1.67; 20 participants; low-certainty evidence) for Rose Bengal staining. Both staining scales range from 0 to 9, with higher scores indicating worse results. The mean change in tear film break-up time was 2.00 seconds longer (95% CI 0.99 to 3.01; 20 participants; low-certainty evidence) in the AS group than in the artificial tears group. Investigators reported no clinically meaningful differences in Schirmer's test scores between groups (mean difference -0.40 mm, 95% CI -2.91 to 2.11; 20 participants; low-certainty evidence). None of these three trials reported tear hyperosmolarity and adverse events.Two trials compared AS versus saline; however, only one trial reported quantitative data for analysis of only one outcome (Rose Bengal staining). Trial investigators of the two studies reported no differences in symptom scores, fluorescein staining scores, tear film break-up times, or Schirmer's test scores between groups at two to four weeks' follow-up. Very low-certainty evidence from one trial suggested that AS might provide some improvement in Rose Bengal staining scores compared with saline after four weeks of treatment; the mean difference in Rose Bengal staining score (range from 0 to 9, with higher scores showing worse results) was -0.60 (95% CI -1.11 to -0.09; 35 participants). Neither trial reported tear hyperosmolarity outcomes. One trial reported adverse events; two of 12 participants had signs of conjunctivitis with negative culture that did resolve. AUTHORS' CONCLUSIONS: Overall, investigators reported inconsistency in possible benefits of AS for improving participant-reported symptoms and other objective clinical measures. There might be some benefit in symptoms with AS compared with artificial tears in the short-term, but we found no evidence of an effect after two weeks of treatment. Well-planned, large, high-quality RCTs are warranted to examine participants with dry eye of different severities by using standardized questionnaires to measure participant-reported outcomes, as well as objective clinical tests and objective biomarkers to assess the benefit of AS therapy for dry eye.

Longitudinal Study of Age-Related Cataract Using Dynamic Light Scattering: Loss of α-Crystallin Leads to Nuclear Cataract Development.

PURPOSE: To conduct a longitudinal study on age-related nuclear cataracts using dynamic light scattering (DLS) to determine if cataract progression is associated with loss of the unbound form of the lens molecular chaperone protein, α-crystallin. DESIGN: Natural history and cohort study. PARTICIPANTS: Patients 30 years of age or older of either gender seeking treatment at the Wilmer Eye Institute Cornea-Cataract Department. METHODS: All patients underwent a comprehensive dilated eye examination every 6 months, including slit-lamp grading of their lenses using the Age-Related Eye Disease Study (AREDS) clinical lens grading system and obtaining an estimate of unbound α-crystallin level in the nucleus, the α-crystallin index (ACI), using the National Aeronautics and Space Administration-National Eye Institute DLS device. We used a random effects statistical model to examine the relationship of lens opacity changes over time with ACI changes. MAIN OUTCOME MEASURES: α-Crystallin Index (ACI) and AREDS nuclear cataract grade. RESULTS: Forty-five patients (66 eyes) 34 to 79 years of age with AREDS nuclear lens grades of 0 to 3.0 were followed up every 6 months for a mean of 19 months (range, 6-36 months). We found that lenses with the lowest baseline levels of ACI had the most rapid progression of cataracts, whereas lenses with higher ACI at baseline had no or slower cataract progression. Lenses that lost α-crystallin at the highest rates during the study also had faster progression of nuclear cataracts than lenses with a slower rate of ACI loss. Kaplan-Meier survival curves showed that lenses with the lowest initial ACI had the highest risk of undergoing cataract surgery. CONCLUSIONS: This longitudinal study corroborates our previous cross-sectional study finding that higher levels of unbound α-crystallin as assessed by ACI are associated with lower risk of cataract formation and that loss of ACI over time is associated with cataract formation and progression. This study suggested that assessment of ACI with the DLS device could be used as a surrogate for lens opacity risk in clinical studies, and for assessing nuclear cataract events in studies where cataract development may be a side effect of a drug or device.

Autologous serum eye drops for dry eye.

BACKGROUND: =Theoretically, autologous serum eye drops (AS) have a potential advantage over traditional therapies based on the assumption that ASserve not only as a lacrimal substitute to provide lubrication, but also contain other biochemical components mimicking natural tears more closely. The application of AS in dry eye treatment has gained popularity as a second-line therapy in the treatment of dry eye.Published studies on the subject indicate that autologous serum could be an effective treatment for dry eye. OBJECTIVES: To evaluate the efficacy and safety of AS compared to artificial tears for treating dry eye. SEARCH METHODS: We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2013, Issue 3),Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE,(January 1950 to April 2013), EMBASE (January 1980 to April 2013), Latin American and Caribbean Literature on Health Sciences(LILACS) (January 1982 to April 2013), themetaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov(www.clinicaltrials.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We also searched the Science Citation Index Expanded database (September 2013) and reference lists of included studies. We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 15 April 2013. SELECTION CRITERIA: We included randomized controlled trials (RCTs) in which AS was compared to artificial tears in the treatment of dry eye in adults. DATA COLLECTION AND ANALYSIS: Two review authors independently screened all titles and abstracts and assessed full-text articles of potentially eligible trials. Two review authors extracted data and assessed the methodological quality and characteristics of the included trials.We contacted investigators for missing data. For both primary and secondary outcomes, we reported mean differences with corresponding 95% confidence intervals(CIs) for continuous outcomes. MAIN RESULTS: We identified four eligible RCTs in which AS was compared with artificial tear treatment or saline in individuals (n = 72 participants)with dry eye of various etiologies (Sjögren's syndrome-related dry eye, non-Sjögren's syndrome dry eye and postoperative dry eye induced by laser-assisted in situ keratomileusis (LASIK)). The quality of the evidence provided by these trials was variable. A majority of the risk of bias domains were judged to have an unclear risk of bias in two trials owing to insufficient reporting of trial characteristics.One trial was considered to have a low risk of bias for most domains while another was considered to have a high risk of bias for most domains. Incomplete outcome reporting and heterogeneity in the participant populations and follow-up periods prevented the inclusion of these trials in a summary meta-analysis. For the primary outcome, improvement in participant-reported symptoms at one month, one trial (12 participants) showed no difference in participant-reported symptoms between 20% AS and artificial tears. Based on the results of two trials in 32 participants, 20% AS may provide some improvement in participant-reported symptoms compared to traditional artificial tears after two weeks of treatment. One trial also showed positive results with a mean difference in tear breakup time (TBUT) of 2.00 seconds (95% CI 0.99 to 3.01 seconds) between 20% AS and artificial tears after two weeks, which were not similar to findings from the other trials. Based on all other objective clinical assessments included in this review, AS was not associated with improvements in aqueous tear production measured by Schirmer's test (two trials, 33 participants), ocular surface condition with fluorescein (four trials, 72 participants) or Rose Bengal staining (three trials, 60 participants), and epithelial metaplasia by impression cytology compared to artificial tears (one trial, 12 participants). Data on adverse effects were not reported by three of the included studies. In one study, there were no serious adverse events reported with the collection of and treatment with AS. AUTHORS' CONCLUSIONS: Overall there was inconsistency in the possible benefits of AS in improving participant-reported symptoms and TBUT and lack of effect based on other objective clinical measures. Well-planned, large, high-quality RCTs are warranted, in different severities of dry eye and using standardized questionnaires to measure participant-reported outcomes and objective clinical tests as well as objective biomarkers to assess the benefit of AS therapy for dry eye.

Six-month effective treatment of corneal graft rejection.

Topical corticosteroid eye drop is the mainstay for preventing and treating corneal graft rejection. While the frequent topical corticosteroid use is associated with risk of intraocular pressure (IOP) elevation and poor patient compliance that leads to graft failure and the requirement for a repeated, high-risk corneal transplantation. Here, we developed dexamethasone sodium phosphate (DSP)-loaded dicarboxyl-terminated poly(lactic acid) nanoparticle (PLA DSP-NP) formulations with relatively high drug loading (8 to 10 weight %) and 6 months of sustained intraocular DSP delivery in rats with a single dosing. PLA DSP-NP successfully reversed early signs of corneal rejection, leading to rat corneal graft survival for at least 6 months. Efficacious PLA DSP-NP doses did not affect IOP and showed no signs of ocular toxicity in rats for up to 6 months. Subconjunctival injection of DSP-NP is a promising approach for safely preventing and treating corneal graft rejection with the potential for improved patient adherence.

ßA3/A1-crystallin is required for proper astrocyte template formation and vascular remodeling in the retina.

Nuc1 is a spontaneous rat mutant resulting from a mutation in the Cryba1 gene, coding for ßA3/A1-crystallin. Our earlier studies with Nuc1 provided novel evidence that astrocytes, which express ßA3/A1-crystallin, have a pivotal role in retinal remodeling. The role of astrocytes in the retina is only beginning to be explored. One of the limitations in the field is the lack of appropriate animal models to better investigate the function of astrocytes in retinal health and disease. We have now established transgenic mice that overexpress the Nuc1 mutant form of Cryba1, specifically in astrocytes. Astrocytes in wild type mice show normal compact stellate structure, producing a honeycomb-like network. In contrast, in transgenics over-expressing the mutant (Nuc1) Cryba1 in astrocytes, bundle-like structures with abnormal patterns and morphology were observed. In the nerve fiber layer of the transgenic mice, an additional layer of astrocytes adjacent to the vitreous is evident. This abnormal organization of astrocytes affects both the superficial and deep retinal vascular density and remodeling. Fluorescein angiography showed increased venous dilation and tortuosity of branches in the transgenic retina, as compared to wild type. Moreover, there appear to be fewer interactions between astrocytes and endothelial cells in the transgenic retina than in normal mouse retina. Further, astrocytes overexpressing the mutant ßA3/A1-crystallin migrate into the vitreous, and ensheath the hyaloid artery, in a manner similar to that seen in the Nuc1 rat. Together, these data demonstrate that developmental abnormalities of astrocytes can affect the normal remodeling process of both fetal and retinal vessels of the eye and that ßA3/A1-crystallin is essential for normal astrocyte function in the retina.

Hypopyon uveitis following LASIK in a patient with ulcerative colitis.

PURPOSE: To present a case of unilateral hypopyon uveitis that began 15 days after uneventful bilateral LASIK in a 24-year-old man with an undisclosed history of ulcerative colitis. METHODS: Case report. RESULTS: The hypopyon uveitis completely resolved after treatment with aggressive topical and oral steroid agents in combination with topical antibiotic coverage. CONCLUSIONS: Although rare, visually significant hypopyon uveitis may arise after LASIK in the setting of ulcerative colitis and positive human leukocyte antigen (HLA) B27. Early recognition and treatment can result in an excellent outcome. The exact relationship between hypopyon uveitis and LASIK is impossible to ascertain.

Accuracy of intraocular lens calculations using the IOLMaster in eyes with long axial length and a comparison of various formulas.

PURPOSE: To evaluate the relationship between eyes with long axial length (AL) and postoperative refractive errors as predicted by various commonly used intraocular lens (IOL) formulas using the Zeiss IOLMaster (Carl Zeiss Meditec, Jena, Germany). DESIGN: Retrospective chart review. PARTICIPANTS: A total of 53 eyes of 36 patients with an AL of more than 27 mm who underwent uncomplicated cataract extraction with IOL implantation. METHODS: Data were obtained from patient charts and the IOLMaster. MAIN OUTCOME MEASURES: The main parameters assessed were AL, preoperative best-corrected visual acuity (BCVA), postoperative BCVA, and mean absolute error (actual postoperative spherical equivalent minus predicted postoperative spherical equivalent). Mean absolute error was calculated using predicted spherical equivalents obtained from the Holladay 1, Holladay 2, SRK/T, Hoffer Q, and Haigis formulas. RESULTS: The Haigis formula was found to be the most accurate in predicting postoperative refractive error in long eyes. The SRK/T formula was the second most accurate, followed by the Holladay 2, then the Holladay 1, then the Hoffer Q. All formulas predicted a more myopic outcome than was actually achieved. CONCLUSIONS: These results suggest using the Haigis, SRK/T, or Holladay 2 formulas for very long eyes. It is also advisable to aim for a more myopic result than is intended.

Descemet-stripping automated endothelial keratoplasty: a successful alternative to repeat penetrating keratoplasty.

BACKGROUND: Although Descemet-stripping automated endothelial keratoplasty has replaced penetrating keratoplasty for primary treatment of endothelial disorders, many patients have already undergone penetrating keratoplasty. It is unclear when repeat penetrating keratoplasty is necessary or when endothelial keratoplasty may restore clarity to a failed graft. DESIGN: Retrospective case series of patients undergoing Descemet-stripping automated endothelial keratoplasty after penetrating keratoplasty by three surgeons at an academic tertiary care centre. PARTICIPANTS: Eight patients with Descemet-stripping automated endothelial keratoplasty after penetrating keratoplasty from 2006 to 2009. METHODS: Microkeratome-prepared Descemet-stripping automated endothelial keratoplasty donor tissue was used. In seven cases, the penetrating keratoplasty bed was neither stripped nor scraped, and in one, scraping only was performed. MAIN OUTCOME MEASURES: Preoperative and 6-month postoperative best-corrected visual acuities in logMAR (logarithm of the minimum angle of resolution). RESULTS: The average pre-Descemet-stripping automated endothelial keratoplasty best-corrected visual acuity was 1.375, and the average best-corrected visual acuity 6months postoperatively was logMAR 1.0, a 2.5-fold improvement in the minimum angle of resolution (P=0.22). Seven of the eight patients showed an improvement in best-corrected visual acuity, and one patient had failure of Descemet-stripping automated endothelial keratoplasty and required penetrating keratoplasty. Five had a postoperative event: one had a gap that resolved spontaneously, three required rebubblings (injections of air only without otherwise repositioning the graft), and one experienced graft failure. CONCLUSIONS: Descemet-stripping automated endothelial keratoplasty can successfully rescue a prior penetrating keratoplasty, even with a fairly high detachment rate. Given these favourable visual outcomes, further study of this promising strategy is justified.

Sunitinib malate-loaded biodegradable microspheres for the prevention of corneal neovascularization in rats.

Corneal neovascularization (NV) predisposes patients to compromised corneal transparency and visional acuity. Sunitinib malate (Sunb-malate) targeting against multiple receptor tyrosine kinases, exerts potent antiangiogenesis. However, the rapid clearance of Sunb-malate eye drops administered through topical instillation limits its therapeutic efficacy and poses a challenge for potential patient compliance. Sunb-malate, the water-soluble form of sunitinib, was shown to have higher intraocular penetration through transscleral diffusion following subconjunctival (SCT) injection in comparison to its sunitinib free base formulation. However, it is difficult to load highly water-soluble drugs and achieve sustained drug release. We developed Sunb-malate loaded poly(D,L-lactic-co-glycolic acid) (PLGA) microspheres (Sunb-malate MS) with a particle size of approximately 15 µm and a drug loading of 7 wt%. Sunb-malate MS sustained the drug release for 30 days under the in vitro infinite sink condition. Subconjunctival (SCT) injection of Sunb-malate MS provided a prolonged ocular drug retention and did not cause ocular toxicity at a dose of 150 µg of active agent. Sunb-malate MS following SCT injection more effectively suppressed the suture-induced corneal NV than either Sunb-malate free drug or the placebo MS. Local sustained release of Sunb-malate through the SCT injection of Sunb-malate MS mitigated the proliferation of vascular endothelial cells and the recruitment of mural cells into the cornea. Moreover, the gene upregulation of proangiogenic factors induced by the pathological process was greatly neutralized by SCT injection of Sunb-malate MS. Our findings provide a sustained release platform for local delivery of tyrosine kinase inhibitors to treat corneal NV.