Recent advances in the management of non-infectious posterior uveitis

AAV-mediated gene therapies for glaucoma and uveitis: are we there yet?

Glaucoma and uveitis are non-vascular ocular diseases which are among the leading causes of blindness and visual loss. These conditions have distinct characteristics and mechanisms but share a multifactorial and complex nature, making their management challenging and burdensome for patients and clinicians. Furthermore, the lack of symptoms in the early stages of glaucoma and the diverse aetiology of uveitis hinder timely and accurate diagnoses, which are a cause of poor visual outcomes under both conditions. Although current treatment is effective in most cases, it is often associated with low patient adherence and adverse events, which directly impact the overall therapeutic success. Therefore, long-lasting alternatives with improved safety and efficacy are needed. Gene therapy, particularly utilising adeno-associated virus (AAV) vectors, has emerged as a promising approach to address unmet needs in these diseases. Engineered capsids with enhanced tropism and lower immunogenicity have been proposed, along with constructs designed for targeted and controlled expression. Additionally, several pathways implicated in the pathogenesis of these conditions have been targeted with single or multigene expression cassettes, gene editing and silencing approaches. This review discusses strategies employed in AAV-based gene therapies for glaucoma and non-infectious uveitis and provides an overview of current progress and future directions.

Clinical Utilisation of Wide-Field Optical Coherence Tomography and Angiography: A Narrative Review

Many important abnormalities of the vitreous, retina and choroid are predominantly located in the peripheral retina. In some retinal diseases with both central and peripheral manifestations, pathological structural or vascular changes can be apparent in the periphery before they are detectable in the central retina. Conventional optical coherence tomography (OCT) and optical coherence tomography angiography (OCT-A) imaging only cover the most posterior 30° of the retina. Wide-field OCT (WF-OCT), though offering detailed cross-sectional imaging of the peripheral retina, is not yet systematically used in clinical practice. This narrative review provides a presentation of the utilisation of WF-OCT and WF-OCT-A in the diagnosis and monitoring of a variety of ophthalmological diseases and discusses the advantages and limitations of the technology. With the rapidly developing technology, multiple WF-OCT and WF-OCT-A devices are now commercially available and enable the clinician to obtain scans within a field of view up to 200°. As detailed in this review, several studies have shown promising results in the application of WF-OCT and WF-OCT-A in diseases of the retina, choroid and vitreous, such as retinal vein occlusion, diabetic retinopathy, ocular oncology, paediatric ophthalmology, uveitis and lesions of the vitreo-retinal interface. In conclusion, WF-OCT and WF-OCT-A can reliably produce high-quality, non-invasive images of the vitreous, retinal, and choroidal structures and vascularity covering the posterior pole as well as the mid and far periphery. These methods can be a valuable part of a multimodal imaging approach in the management of a variety of ocular conditions. Future studies are warranted to investigate the patient outcome benefits of implementation of WF-OCT and WF-OCT-A imaging in a real-life clinical setting.

Assessment of choriocapillaris and choroidal vascular changes in posterior uveitis using swept-source wide-field optical coherence tomography angiography

PURPOSE

To evaluate choriocapillaris (CC) and choroidal vascular changes in patients with posterior uveitis using swept-source (SS) wide-field optical coherence tomography angiography (OCTA).

METHOD

Consecutive patients with posterior uveitis were evaluated using 3×3 mm and 12×12 mm OCTA scan patterns and montage images of 5×12×12 mm or 2×15×9 mm, covering approximately 70°-90° of the retina. The images were quantitatively and qualitatively analysed and compared with healthy controls.

RESULTS

Eighty-six eyes of 56 patients with posterior uveitis (mean age 45.2±19.9 years; 58.9% female), and 38 eyes of 19 age-matched healthy controls (57.9% female) were included. The mean perfusion density (PD) in 3×3 mm and 12×12 mm CC scans was significantly lower in eyes with posterior uveitis compared with those of healthy controls. However, no significant difference in the mean PD of choroidal scans was found comparing eyes with posterior uveitis and healthy controls. The mean PD in eyes with active disease was significantly higher compared with the inactive eyes on 12×12 mm choroidal scans (55.61% vs 51.25%, p=0.02), while no difference was found in the CC slabs.

CONCLUSION

CC and choroidal assessment using OCTA provides useful information in patients with posterior uveitis. SS-OCTA metrics of the CC and choroidal slabs are promising tools in uveitis patients in the future.

TRIAL REGISTRATION NUMBER

NCT02811536.

Ophthalmological Manifestations in Inflammatory Bowel Diseases: Keep an Eye on It

BACKGROUND AND AIMS

Inflammatory bowel diseases (IBD) are multifactorial chronic inflammatory disorders affecting the gastrointestinal tract. However, a broad spectrum of extraintestinal manifestations (EIMs) is associated with IBD, affecting several organs and systems, such as the skin, musculoskeletal and hepatobiliary systems, and, not least, the eye. Approximately 10% of IBD patients can develop ocular EIMs (O-EIMs) with a higher prevalence in Crohn's disease (CD). Eye-redness, photophobia, pain, and blurred vision are the common symptoms, with a wide rate of severity and clinical impact on the quality of life. This narrative review aims to summarize the prevalence, pathogenesis, and current evidence-based management of O-EIMs, underlying the importance of a holistic approach and specialties collaboration for a prompt diagnosis and treatment.

METHODS

PubMed was searched up to December 2023 to identify relevant studies investigating the pathogenesis, epidemiology, and treatment of O-EIMs in IBD patients.

RESULTS

The mechanisms underlying O-EIMs are partially unknown, encompassing immune dysregulation, shared antigens between the eye and the gut, genetic predisposition, and systemic inflammation driven by high levels of interleukins and cytokines in IBD patients. The complexity of O-EIMs' pathogenesis reflects in the management of these conditions, varying from topical and systemic steroids to immunomodulatory molecules and biologic therapy, such as anti-tumor necrosis factor (TNF)-alpha. A multidisciplinary approach is the backbone of the management of O-EIMs.

Pathogenesis and current therapies for non-infectious uveitis

Non-infectious uveitis (NIU) is a disorder with various etiologies and is characterized by eye inflammation, mainly affecting people of working age. An accurate diagnosis of NIU is crucial for appropriate therapy. The aim of therapy is to improve vision, relieve ocular inflammation, prevent relapse, and avoid treatment side effects. At present, corticosteroids are the mainstay of topical or systemic therapy. However, repeated injections are required for the treatment of chronic NIU. Recently, new drug delivery systems that may ensure intraocular delivery of therapeutic drug levels have been highlighted. Furthermore, with the development of immunosuppressants and biologics, specific therapies can be selected based on the needs of each patient. Immunosuppressants used in the treatment of NIU include calcineurin inhibitors and antimetabolites. However, systemic immunosuppressive therapy itself is associated with adverse effects due to the inhibition of immune function. In patients with refractory NIU or those who cannot tolerate corticosteroids and immunosuppressors, biologics have emerged as alternative treatments. Thus, to improve the prognosis of patients with NIU, NIU should be managed with different drugs according to the response to treatment and possible side effects.

Combined Therapy of Experimental Autoimmune Uveitis by a Dual-Drug Nanocomposite Formulation with Berberine and Dexamethasone

Purpose

Autoimmune uveitis is a kind of sight-threatening ocular and systemic disorders. Recent treatments on autoimmune uveitis still remain many limitations due to extreme complexity and undetermined pathogenesis. In this study, a novel dual-drug nanocomposite formulation is developed to treat experimental autoimmune uveitis by a combined and sustained therapy method.

Methods

The dual-drug nanocomposite formulation is constructed by integrating berberine (BBR)-loaded mesoporous silica nanoparticles (MSNs) into dexamethasone (DEX)-loaded thermogel (BBR@MSN-DEX@Gel). The BBR@MSN-DEX@Gel is characterized by transmission electron microscopy, dynamic light scattering, Fourier transform infrared spectrometer and rheometer. The in vitro drug release profile, cytotoxicity and anti-inflammation effectiveness of BBR@MSN-DEX@Gel on lipopolysaccharide-stimulated human conjunctival epithelial cells are investigated. After the in vivo drug release profile and biosafety of the dual-drug nanocomposite formulation are confirmed, its treatment effectiveness is fully assessed based on the induced experimental autoimmune uveitis (EAU) Lewis rat's model.

Results

The dual-drug nanocomposite formulation has good injectability and thermosensitivity, suitable for administration by an intravitreal injection. The BBR@MSN-DEX@Gel has been found to sustainably release both drugs for up to 4 weeks. The carrier materials have minimal in vitro cytotoxicity and high in vivo biosafety. BBR@MSN-DEX@Gel presents obviously anti-inflammatory effectiveness in vitro. After administration of BBR@MSN-DEX@Gel into Lewis rat's eye with EAU by an intravitreal injection, the nanocomposite formulation significantly suppresses inflammatory reaction of autoimmune uveitis via a dual-drug combined and sustained therapy method, compared with the equivalent dose of single-component formulations.

Conclusion

BBR@MSN-DEX@Gel serves as a promising dual-drug nanocomposite formulation for future treatment of autoimmune uveitis.

Efficacy of 0.19 mg Fluocinolone Acetonide Implant in Non-infectious Posterior Uveitis Evaluated as Area Under the Curve

Introduction

This study reports the outcomes of fluocinolone acetonide intravitreal implant (FAc, Iluvien^®, SIFI, Italy) in patients affected by macular edema secondary to chronic non-infectious uveitis of the posterior segment (NIU-PS).

Methods

This was a retrospective study of patients with NIU-PS and macular thickening undergoing FAc implant at San Raffaele Hospital (Milan, Italy). Clinical data, including best-corrected visual acuity (BCVA), intraocular pressure (IOP), and central macular thickness (CMT), were collected at the time of FAc administration (baseline) and at 1, 6, and 12 months. The area under the curve (AUC) of the BCVA (AUC_BCVA) and CMT (AUC_CMT) was correlated with baseline factors; β estimates and 95% confidence interval (CI) are provided.

Results

Ten eyes of seven patients (60 ± 12 years; 4 male, 57%) were included. The BCVA significantly improved from month 6 (p = 0.03). The CMT improved from month 1 and was persistently lower than baseline until month 12 (p < 0.001). The AUC_BCVA correlated with baseline BCVA (β = 2.5 logMAR; 95% CI 1.59–3.41; p < 0.001), while the mean AUC_CMT positively correlated with the baseline CMT (β = 2.1 μm; 95% CI 0.41–3.80; p = 0.02). No adverse events were recorded over 1 year.

Conclusions

Better visual acuity at the time of FAc administration was associated with better visual function after FAc. Less severe macular edema correlated with better anatomic response. The FAc implant was a safe option for resolving macular edema secondary to NIU-PS.