Intraocular Injection Research Articles

Role of bevacizumab intraocular injection in the management of neovascular glaucoma.

To assess the long-term effects of intraocular bevacizumab (Avastin) injections as an adjunctive drug to manage patients with neovascular glaucoma (NVG). A retrospective study was conducted consisting of 34 eyes with secondary NVG caused by proliferative diabetic retinopathy (n=25), ischemic central retinal vein occlusion (n=8), and retinal ischemia resulting from persistent detachment (n=1) were managed by intraocular injections of bevacizumab (1.25 mg/0.05 mL), in addition to other treatments. The main outcome measure was the change in the degree of iris neovascularization. Secondary outcomes included intraocular pressure and the number of additional interventions or antiglaucoma medications administered after injection. All patients were followed-up for at least 12mo. At the last follow-up, complete regression of rubeosis irides was detectable in 13 (38.2%) eyes and incomplete regression in 21 eyes (61.8%). The mean intraocular pressure was 45.32±7.185 mm Hg at baseline and significantly decreased to 26.15±5.679 mm Hg at the last follow-up visit (P=0.000005). Patients received an average of 4.97 injections. As additional treatments, 12 eyes (35%) received laser photocoagulation and 6 eyes (18%) underwent retinocryopexy. No further treatment was needed in 16 eyes (47.1%). Intravitreal bevacizumab injection can have a favorable effect in controlling intraocular pressure and pain control in patients with NVG because it decreases the angiogenesis and helps to augment the results of conventional procedures. The primary cause of retinal ischemia should be always targeted.

Visual Disfunction due to the Selective Effect of Glutamate Agonists on Retinal Cells.

One of the causes of nervous system degeneration is an excess of glutamate released upon several diseases. Glutamate analogs, like N-methyl-DL-aspartate (NMDA) and kainic acid (KA), have been shown to induce experimental retinal neurotoxicity. Previous results have shown that NMDA/KA neurotoxicity induces significant changes in the full field electroretinogram response, a thinning on the inner retinal layers, and retinal ganglion cell death. However, not all types of retinal neurons experience the same degree of injury in response to the excitotoxic stimulus. The goal of the present work is to address the effect of intraocular injection of different doses of NMDA/KA on the structure and function of several types of retinal cells and their functionality. To globally analyze the effect of glutamate receptor activation in the retina after the intraocular injection of excitotoxic agents, a combination of histological, electrophysiological, and functional tools has been employed to assess the changes in the retinal structure and function. Retinal excitotoxicity caused by the intraocular injection of a mixture of NMDA/KA causes a harmful effect characterized by a great loss of bipolar, amacrine, and retinal ganglion cells, as well as the degeneration of the inner retina. This process leads to a loss of retinal cell functionality characterized by an impairment of light sensitivity and visual acuity, with a strong effect on the retinal OFF pathway. The structural and functional injury suffered by the retina suggests the importance of the glutamate receptors expressed by different types of retinal cells. The effect of glutamate agonists on the OFF pathway represents one of the main findings of the study, as the evaluation of the retinal lesions caused by excitotoxicity could be specifically explored using tests that evaluate the OFF pathway.

Comparison of three regional anaesthetic techniques for infraorbital or maxillary nerve block in cats: a cadaveric study.

ObjectivesThe maxillary nerve courses very close to the globe, rendering cats – with their large eyes – at risk of globe penetration during infraorbital or maxillary nerve blocks. Therefore, the goals of the study were to compare the distribution and potential complications of three infraorbital or maxillary regional injection techniques.MethodsTwenty-three bilateral maxillae of cat cadavers were used in a randomised blinded trial. Each maxilla was injected with a 0.2 ml 1:1 mixture of lidocaine 2% and a contrast medium by one of three injection techniques: infraorbital foramen (IOF; n = 14); infraorbital canal (IOC; n = 16); or maxillary foramen (MF; transpalpebral approach; n = 16) using a 25 G 1.6 cm needle. CT imaging of each cadaver head was performed before and after injections. A radiologist scored injectate distribution (none [0], mild [1], moderate [2], large [3]) in four locations: rostral, central and caudal IOC, and at the MF, for which the distribution side was also determined. Comparisons were performed with ordinal logistic mixed effects (P <0.05).ResultsThe median (range) total distribution score of the IOC and MF technique were significantly higher compared with the IOF technique (6.5 [4–12], 4 [2–8] and 0 [0–10], respectively). The total IOC score was also significantly higher compared with the MF technique. Injectate distribution at the MF was significantly more central following IOC injection compared with MF injection, which distributed centrolaterally. None of the techniques resulted in intraocular injection.Conclusions and relevanceThe IOC and MF techniques produced a satisfactory spread of the mixture that could result in effective maxillary anaesthesia in cats. Further studies are required to determine the effectiveness and safety of these techniques.

An Innovative Technique for Fluid Infiltration Using Double-Bent Needle.

Local infiltration of tumescent fluid and saline is required in various surgical procedures such as liposuction and hair transplant surgery. The use of small-caliber needles requires more time and power for injection, especially in the superficial planes of the skin.1 The use of large-caliber needles has a few drawbacks. These include painful infiltration and lack of control of the volume injected. Moreover, there are high chances of needle injections into the vessels, and intravascular injections may occasionally result. Various techniques have been developed to avoid the complication. One technique is to use blunt needles or cannulas or short needles. Another is to bend the needle and keep the full length of the needle parallel to the skin to avoid injuring deeper structures (Fig. 1).Fig. 1.: Single-bent (above) and double-bent (below) needles.We have developed a new technique in which large-caliber needles can be used to inject larger volumes without any fear of injuring deeper structures or risking intravascular injections, as described below. [See Video 1 (online), which demonstrates how to make a double-bent needle.] {"href":"Single Video Player","role":"media-player-id","content-type":"play-in-place","position":"float","orientation":"portrait","label":"Video 1.","caption":"Method for making a double-bent needle.","object-id":[{"pub-id-type":"doi","id":""},{"pub-id-type":"other","content-type":"media-stream-id","id":"1_elkyvaex"},{"pub-id-type":"other","content-type":"media-source","id":"Kaltura"}]} Hold the needle in the needle holder at about 3 to 4 mm from the tip, with the eye of needle facing up. Bend the needle at a right angle in a counterclockwise direction to create the first bend (point A) (Fig. 1, above). Hold the needle at about 2 to 3 mm proximal to point A and bend in a clockwise position at a right angle to create the second bend (point B) (Fig. 1, below). The direction of the distal part can be adjusted as well (Fig. 1, below). The use of a bent needle is not new in the medical literature. The bent needle is used in dentistry for intraoral nerve blocks and for supraclavicular regional blocks.2,3 The bent needle with broken tip is also used in plastic surgical procedures for irrigation. Similarly, the double-bent needle has been used in intraocular injections as well.4 We have developed this new technique to inject large amounts of fluid without any fear of intravascular injection, especially in the subcutaneous plane. In order to maximize safety, the eye at the bevel is faced upward. [See Video 2 (online), which shows application of the double-bent needle.] The bending of the needle at two points also decreases the lumen of the needle, which decreases the flow rate as well. The part between the two bend serves as depth control. {"href":"Single Video Player","role":"media-player-id","content-type":"play-in-place","position":"float","orientation":"portrait","label":"Video 2.","caption":"Clinical application of double-bent needle.","object-id":[{"pub-id-type":"doi","id":""},{"pub-id-type":"other","content-type":"media-stream-id","id":"1_8mnc7h8g"},{"pub-id-type":"other","content-type":"media-source","id":"Kaltura"}]} Avoid a second attempt to bend or twist the needle, as that may weaken the needle and it may break and can cause needle tip impaction. DISCLOSURE The authors have no financial interest to declare in relation to the content of this article.

Start codon disruption with CRISPR/Cas9 prevents murine Fuchs' endothelial corneal dystrophy.

A missense mutation of collagen type VIII alpha 2 chain (COL8A2) gene leads to early-onset Fuchs' endothelial corneal dystrophy (FECD), which progressively impairs vision through the loss of corneal endothelial cells. We demonstrate that CRISPR/Cas9-based postnatal gene editing achieves structural and functional rescue in a mouse model of FECD. A single intraocular injection of an adenovirus encoding both the Cas9 gene and guide RNA (Ad-Cas9-Col8a2gRNA) efficiently knocked down mutant COL8A2 expression in corneal endothelial cells, prevented endothelial cell loss, and rescued corneal endothelium pumping function in adult Col8a2 mutant mice. There were no adverse sequelae on histology or electroretinography. Col8a2 start codon disruption represents a non-surgical strategy to prevent vision loss in early-onset FECD. As this demonstrates the ability of Ad-Cas9-gRNA to restore the phenotype in adult post-mitotic cells, this method may be widely applicable to adult-onset diseases, even in tissues affected with disorders of non-reproducing cells.

Intraocular pressure and injection forces during intravitreal injection into enucleated porcine eyes

Injection of biological molecules into the intravitreous humor is of increasing interest for the treatment of posterior segment eye diseases such as age-related degenerative macular degeneration. The injection volume is limited by an increase in intraocular pressure (IOP) and 50–100 µL are typically used for most intravitreally (IVT) applied commercial products. Direct measurement of IOP is difficult and has not been studied dependent on solution properties and injection rates. We used an instrumental set-up to study IOP ex vivo using healthy enucleated porcine eyes. IOP was determined as a function of injection volume for viscosities between 1 and 100 mPas, injection rates of 0.1, 1, and 1.5 mL/min, and needle length and diameter (27/30G and 0.5/0.75″) using Dextran solutions. IOP increased exponentially for injection volumes larger than 100 µL. We did not observe differences in IOP dependent on viscosity, injection rate, and needle diameter. However, variability increased significantly for injection volumes larger than 100 µL and, unexpectedly, declined with higher viscosities. We demonstrate that the exponential increase in IOP is not reflected by injection force measurements for typical configurations that are used for IVT application. The present findings may guide injection volumes for intravitreal injection and inform injection force considerations during technical drug product development.

Emerging therapies and their delivery for treating age-related macular degeneration.

Age-related macular degeneration (AMD) is the most common cause of blindness in the Western world and is characterised in its latter stages by retinal cell death and neovascularisation and earlier stages with the loss of parainflammatory homeostasis. Patients with neovascular AMD (nAMD) are treated with frequent intraocular injections of anti-vascular endothelial growth factor (VEGF) therapies, which are not only unpopular with patients but carry risks of sight-threatening complications. A minority of patients are unresponsive with no alternative treatment available, and some patients who respond initially eventually develop a tolerance to treatment. New therapeutics with improved delivery methods and sustainability of clinical effects are required, in particular for non-neovascular AMD (90% of cases and no current approved treatments). There are age-related and disease-related changes that occur which can affect ocular drug delivery. Here, we review the latest emerging therapies for AMD, their delivery routes and implications for translating to clinical practice. LINKED ARTICLES: This article is part of a themed issue on Inflammation, Repair and Ageing. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v179.9/issuetoc.

Genetically-Caused Blindness Reversed with Single Injection of Antisense Therapeutic

Clinical OMICsVol. 8, No. 3 NewsFree AccessGenetically-Caused Blindness Reversed with Single Injection of Antisense TherapeuticPublished Online:18 Jun 2021https://doi.org/10.1089/clinomi.08.03.04AboutSectionsPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions Back To Publication ShareShare onFacebookTwitterLinked InRedditEmail A patient with a genetic form of childhood blindness gained vision for more than a year after receiving a single injection of an experimental antisense oligonucleotide, sepofarsen, into the eye.The clinical trial was conducted by researchers at the University of Pennsylvania. According to their study, which appeared in Nature Medicine, the treatment led to marked changes at the fovea, the most important locus of human central vision.Almost a dozen antisense treatments have been approved by the FDA to date. Almost all of these are for orphan diseases, including the drug used in this study. It targets Leber congenital amaurosis (LCA), but is specifically designed for LCA patients with the CEP290 mutation – one of the more commonly implicated gene variants. Patients with this form of LCA suffer from severe visual impairment, typically beginning in infancy.In an international clinical trial led by Penn Medicine researchers Artur Cideciyan, Ph.D., and Samuel Jacobson, M.D., Ph.D., participants received an intraocular injection of sepofarsen. This oligonucleotide works by increasing normal CEP290 protein levels in the eye's photoreceptors.In a previous study, Cideciyan, Jacobson, and collaborators found that injections of sepofarsen every three months resulted in continued vision gains in ten patients.The eleventh patient, whose results are reported in this study, had only one injection and was examined over a 15-month period. Prior to treatment, the patient had reduced visual acuity, small visual fields, and no night vision.After a single injection, more than a dozen measurements of visual function and retinal structure showed large improvements supporting a biological effect from the treatment, which were retained at month 15. The patient's vision reached a peak effect after month two.FiguresReferencesRelatedDetails Volume 8Issue 3May 2021 InformationCopyright © GEN PublishingTo cite this article:Clinical OMICs.May 2021.5-5.http://doi.org/10.1089/clinomi.08.03.04Published in Volume: 8 Issue 3: June 18, 2021PDF download

Vascular Expression of Permeability-Resistant Occludin Mutant Preserves Visual Function in Diabetes.

Diabetic retinopathy is one of the leading causes of vision loss and blindness. Extensive preclinical and clinical evidence exists for both vascular and neuronal pathology. However, the relationship of these changes in the neurovascular unit and impact on vision remains to be determined. Here, we investigate the role of tight junction protein occludin phosphorylation at S490 in modulating barrier properties and its impact on visual function. Conditional vascular expression of the phosphorylation-resistant Ser490 to Ala (S490A) form of occludin preserved tight junction organization and reduced vascular endothelial growth factor (VEGF)-induced permeability and edema formation after intraocular injection. In the retinas of streptozotocin-induced diabetic mice, endothelial-specific expression of the S490A form of occludin completely prevented diabetes-induced permeability to labeled dextran and inhibited leukostasis. Importantly, vascular-specific expression of the occludin mutant completely blocked the diabetes-induced decrease in visual acuity and contrast sensitivity. Together, these results reveal that occludin acts to regulate barrier properties downstream of VEGF in a phosphorylation-dependent manner and that loss of inner blood-retinal barrier integrity induced by diabetes contributes to vision loss.

Antimicrobial nanomedicine for ocular bacterial and fungal infection.

Ocular infection induced by bacteria and fungi is a major cause of visual impairment and blindness. Topical administration of antibiotics remains the first-line treatment, as effective eradication of pathogens is the core of the anti-infection strategy. Whereas, eye drops lack efficiency and have relatively low bioavailability. Intraocular injection may cause concurrent ocular damage and secondary infection. In addition, antibiotic-based management can be limited by the low sensitivity to multidrug-resistant bacteria. Nanomedicine is proposed as a prospective, effective, and noninvasive platform to mediate ocular delivery and combat pathogen or even resistant strains. Nanomedicine can not only carry antimicrobial agents to fight against pathogens but also directly active microbicidal capability, killing pathogens. More importantly, by modification, nanomedicine can achieve enhanced residence time and release time on the cornea, and easy penetration through corneal tissues into anterior and posterior segments of the eye, thus improving the therapeutic effect for ocular infection. In this review, several categories of antimicrobial nanomedicine are systematically discussed, where the efficiency and possibility of further embellishment and improvement to adapt to clinical use are also investigated. All in all, novel antimicrobial nanomedicine provides potent and prospective ways to manage severe and refractory ocular infections.

Significant improvement of Age-Related Macular Degeneration with Melanin Precursors (QIAPI 1®). Case Report

Age-related macular degeneration is the first cause of blindness in cold countries in the last 70 years ago or more. In spite expensive therapeutics strategies like intraocular injections, so far, the incidence and prevalence of ARMD cannot be improved significantly. In this case report, we demonstrate that melanin is a fundamental part of macular biology and once is attended the recovery both anatomical and functional is significant.

Significant improvement of Age-Related Macular Degeneration with Melanin Precursors (QIAPI 1®). Case Report

Age-related macular degeneration is the first cause of blindness in cold countries in the last 70 years ago or more. In spite expensive therapeutics strategies like intraocular injections, so far, the incidence and prevalence of ARMD cannot be improved significantly. In this case report, we demonstrate that melanin is a fundamental part of macular biology and once is attended the recovery both anatomical and functional is significant.

High dose expression of heme oxigenase-1 induces retinal degeneration through ER stress-related DDIT3

BackgroundOxidative stress is a common cause of neurodegeneration and plays a central role in retinal degenerative diseases. Heme oxygenase-1 (HMOX1) is a redox-regulated enzyme that is induced in neurodegenerative diseases and acts against oxidative stress but can also promote cell death, a phenomenon that is still unexplained in molecular terms. Here, we test whether HMOX1 has opposing effects during retinal degeneration and investigate the molecular mechanisms behind its pro-apoptotic role.MethodsBasal and induced levels of HMOX1 in retinas are examined during light-induced retinal degeneration in mice. Light damage-independent HMOX1 induction at two different expression levels is achieved by intraocular injection of different doses of an adeno-associated virus vector expressing HMOX1. Activation of Müller glial cells, retinal morphology and photoreceptor cell death are examined using hematoxylin-eosin staining, TUNEL assays, immunostaining and retinal function are evaluated with electroretinograms. Downstream gene expression of HMOX1 is analyzed by RNA-seq, qPCR examination and western blotting. The role of one of these genes, the pro-apoptotic DNA damage inducible transcript 3 (Ddit3), is analyzed in a line of knockout mice.ResultsLight-induced retinal degeneration leads to photoreceptor degeneration and concomitant HMOX1 induction. HMOX1 expression at low levels before light exposure prevents photoreceptor degeneration but expression at high levels directly induces photoreceptor degeneration even without light stress. Photoreceptor degeneration following high level expression of HMOX1 is associated with a mislocalization of rhodopsin in photoreceptors and an increase in the expression of DDIT3. Genetic deletion of Ddit3 in knockout mice prevents photoreceptor cell degeneration normally resulting from high level HMOX1 expression.ConclusionThe results reveal that the expression levels determine whether HMOX1 is protective or deleterious in the retina. Furthermore, in contrast to the protective low dose of HMOX1, the deleterious high dose is associated with induction of DDIT3 and endoplasmic reticulum stress as manifested, for instance, in rhodopsin mislocalization. Hence, future applications of HMOX1 or its regulated targets in gene therapy approaches should carefully consider expression levels in order to avoid potentially devastating effects.

Clinical ophtalmo-pharmacology. Looking ahead.

Clinical ophtalmo-pharmacology. Looking ahead.

An Iris Tumor Secondary to Talaromyces Marneffei Infection in a Patient with AIDS and Syphilis

ABSTRACT Purpose To report a case of iris tumor secondary to Talaromyces marneffei infection in a patient with AIDS and syphilis. Case report A 25-year-old man presented with gradual vision decrease in the right eye for 2 months. Ocular examination revealed best-corrected visual acuity (BCVA) of 0.12 and a vascularized and solid tumor at inferotemporal iris base in the right eye. There were some papulonecrotic skin lesions. Both serum treponema pallidum particle agglutination and human immunodeficiency virus antibody were positive. Non-target metagenome next-generation sequencing detected Talaromyces marneffei in the skin lesion and aqueous humor. After 8 weeks of oral voriconazole and fluconazole eyedrop treatment, the iris tumor completely subsided, and the BCVA improved to 1.0. Conclusion Talaromyces marneffei infection may present as an iris tumor. Metagenome next-generation sequencing is helpful in diagnosis. Oral and topical anti-fungus therapy was sufficient to regress the disease without intraocular injection.

AAV Induced Expression of Human Rod and Cone Opsin in Bipolar Cells of a Mouse Model of Retinal Degeneration

Vision loss caused by inherited retinal degeneration affects millions of people worldwide, and clinical trials involving gene supplementation strategies are ongoing for select forms of the disease. When early therapeutic intervention is not possible and patients suffer complete loss of their photoreceptor cells, there is an opportunity for vision restoration techniques, including optogenetic therapy. This therapy provides expression of light-sensitive molecules to surviving cell types of the retina, enabling light perception through residual neuronal pathways. To this end, the bipolar cells make an obvious optogenetic target to enable upstream processing of visual signal in the retina. However, while AAV transduction of the bipolar cells has been described, the expression of human opsins in these cell types within a model of retinal degeneration (rd1) has been less successful. In this study, we have expanded the optogenetic toolkit and shown successful expression of human rhodopsin driven by an ON-bipolar cell promoter (Grm6) in the rd1 mouse model using modified AAV capsids (AAV2.4YF, AAV8.BP2, and AAV2.7m8) delivered via intraocular injection. We also show the first presentation of ectopic expression of human cone opsin in the bipolar cells of rd1 mice. These data provide evidence of an expansion of the optogenetic toolkit with the potential to restore useful visual function, setting the stage for future trials in human patients.

Upregulation of long non-coding RNA SNHG16 promotes diabetes-related RMEC dysfunction via activating NF-κB and PI3K/AKT pathways

Diabetic retinopathy (DR) is a severe diabetes-induced eye disease, in which its pathological phenomena basically include abnormal proliferation, migration, and angiogenesis of microvascular endothelial cells in the retina. Long non-coding RNAs (lncRNAs) have been proven to be important regulators in various biological processes, but their participation in DR remains largely undiscovered. In the present study, we aimed to unveil the role of lncRNA small nucleolar RNA host gene 16 (SNHG16) in regulating the functions of human retinal microvascular endothelial cells (hRMECs) under a high-glucose (HG) condition. We found that SNHG16 expression was significantly upregulated in hRMECs treated with HG. Functionally, SNHG16 could facilitate hRMEC proliferation, migration, and angiogenesis. Moreover, SNHG16 was associated with nuclear factor κB (NF-κB) and phosphatidylinositol 3-kinase (PI3K)/AKT pathways. Mechanistically, SNHG16 could promote hRMEC dysfunction by sequestering microRNA (miR)-146a-5p and miR-7-5p to act as a competing endogenous RNA (ceRNA) with interleukin-1 receptor-associated kinase 1 (IRAK1) and insulin receptor substrate 1 (IRS1). In conclusion, our results illustrated the potential role of SNHG16 in facilitating hRMEC dysfunction under HG treatment, providing a novel approach for DR therapy.

Refractive outcomes after intravitreal injection of antivascular endothelial growth factor versus laser photocoagulation for retinopathy of prematurity: a meta-analysis

ObjectiveTo determine the effects of the intraocular injection of antivascular endothelial growth factor (anti-VEGF) drugs on the refractive status of infants with retinopathy of prematurity (ROP).DesignSystematic review and meta-analysis of...

Intraocular Injection of HyStem Hydrogel Is Tolerated Well in the Rabbit Eye.

Purpose: To determine the long-term biocompatibility of HyStem® hydrogel in the rabbit eye for use as a carrier for cell or drug delivery into the ocular space. Methods: HyStem hydrogel formulation solidifies ∼20 min after reconstitution, thus can potentially form a solid deposit after injection in situ. To study the ocular disposition of fluorescein-labeled HyStem, we delivered 50 μL/eye over 1 min into the vitreous space of the rabbit. We used 3 Dutch-Belted and 3 New Zealand-pigmented rabbits, all females, delivered the gel into the right eyes, and injected 50 μL BSS Plus into the left eyes as a control. Retinal morphology was assessed by optical coherence tomography (OCT) and white light fundus photography. Fluorescence fundus photography enabled measurement of the clearance of the labeled hydrogel from the posterior chamber. Visual function was evaluated using flash and flicker electroretinography (ERG) pre- and postinjection and at weekly intervals thereafter for 6 weeks. Retinal immunohistochemistry for microglial inflammatory markers was carried out with antiglial fibrillary acidic protein (GFAP) antibody, isolectin B4 (IB4), and 4',6-diamidino-2-phenylindole (DAPI). Results: The gel was successfully delivered into the vitreous space without the formation of a discrete retinal deposit. Fundus imaging, OCT measurements of retinal thickness, and immunohistochemical data indicated an absence of retinal inflammation, and ERG indicated no impact on retinal function. The half-time of HyStem clearance calculated from the loss of fundus fluorescence was 3.9 days. Conclusions: HyStem hydrogel appears to be biocompatible in the ocular space of a large eye and safe for long-term intraocular application.

Laser irradiation of ocular tissues to enhance drug delivery

Scleral and corneal membranes represent substantial barriers against drug delivery to the eye. Conventional hypodermic needles-based intraocular injections are clinically employed to overcome these barriers. This study, for the first time, investigated a non-invasive alternative to intraocular injections by laser irradiation of ocular tissues. The P.L.E.A.S.E.® laser device was applied on excised porcine scleral and corneal tissues, which showed linear relationships between depths of laser-created micropores and laser fluences at range 8.9–444.4 J/cm2. Deeper and wider micropores were observed in scleral relative to corneal tissues. The permeation of rhodamine B and fluorescein isothiocyanate (FITC)-dextran were investigated through ocular tissues at different laser parameters (laser fluences 0–44.4 J/cm2 and micropore densities 7.5 and 15%). Both molecules showed enhanced permeation through ocular tissues on laser irradiation. Maximum transscleral permeation of the molecules was attained at laser fluence 8.9 J/cm2 and micropore density 15%. Transcorneal permeation of rhodamine B increased with increasing either laser fluence or micropore density, while that of FITC-dextran was not affected by either parameter. The transscleral water loss increased significantly after laser irradiation then returned to the baseline values within 24 h, indicating healing of the laser-created micropores. Laser irradiation is a promising technique to enhance intraocular delivery of both small and large molecule drugs.