Hossam Mohamed Moharram

Purpose Topical corticosteroids administration is commonly used for management of various ocular conditions especially those affecting the anterior segment of the eye. Poor solubility and limited pre-corneal residence time result in insufficient drug penetration to the outer (cornea and conjunctival-scleral) coats of the eye. This study aimed to prepare and evaluate cubosomes for prolonging residence time and enhancing ocular bioavailability of BDP. Methods GMO-cubosomes were prepared using the top-down technique. Two stabilizers were investigated: poloxamer 407 and solulan C24. Particle size, EE %, polarized-light microscopy, TEM, in vitro release, transcorneal permeation, BCOP, histopathology and in vivo evaluation for treatment of uveitis in a rabbits’ model were studied. Results The prepared cubosomes were of nano-sizes (100 nm – 278 nm); EE% was around 94%. The cubosomes were confirmed by visualizing the “Maltese crosses” textures. Transcorneal permeation was significantly (p < 0.05) improved, compared to BDP-suspension (the control formulation). The optimized cubosomes F1P was incorporated in CMC gel (Cubo-gel). The prepared Cubo-gel formulations showed better rheological characteristics and high ocular tolerability. Superior anti-inflammatory properties were recorded for the Cubo-gel for treatment of endotoxin-induced uveitis in the rabbit model when compared to the control BDP-suspension. Conclusions Transcorneal permeation parameters P_app and flux and AUC_0-10h markedly enhanced by up to 4-, 5.8-and 5.5-fold respectively, compared to the control BDP-suspension formulation. This study suggested that cubosomes/Cubo-gel could be an auspicious ocular delivery system for BDP that was able to effectively treat uveitis (a disease of the posterior segment of the eye).

Background: Epiretinal membranes (ERMs) have been reported after pars plana vitrectomy (PPV) for rhegmatogenous retinal detachment (RRD). Peeling of the internal limiting membrane (ILM) can prevent post-PPV ERM formation but has a potential negative impact on macular structure and function. Purpose: To investigate the anatomical and functional outcomes of ILM peeling during PPV for primary RRD. Methods: This was a prospective nonrandomized study that included 60 eyes of 60 patients with a primary macula-off RRD and less than grade C proliferative vitreoretinopathy (PVR). Eyes were allocated into 2 groups; Group A underwent PPV without ILM peeling and Group B had ILM peeling. At postoperative month 6, all patients underwent retinal imaging using spectral domain optical coherence tomography (OCT) and OCT angiography and macular function was assessed using multifocal electroretinogram (mfERG). Baseline characteristics and postoperative anatomical and visual outcomes were recorded and statistically analyzed. Results: We enrolled 30 eyes of 30 patients in each group. In Group A, mean age was 44.6 years, while the mean age of Group B patients was 49.9 years. Postoperative LogMAR visual acuity was significantly better in Group A than in Group B (p < 0.001). ERMs were demonstrated on OCT in 13.3% of Group A and none of Group B patients (p = 0.04). Retinal dimples were found in 53.3% of Group B and none of Group A eyes (p < 0.001). OCTA showed a greater vessel density of the superficial capillary plexus (SCP) in Group A compared to Group B eyes (p = 0.046), while no difference was found regarding deep capillary vessel density (p = 0.7). Mean amplitude of mfERG P1 wave was significantly higher in Group A eyes than in Group B (p = 0.002). Both the SCP vessel density and P1 amplitude were positively correlated with visual acuity (p < 0.001). Conclusion: This study suggests that ILM peeling prevents ERM development in eyes undergoing PPV for uncomplicated macula-off RRD, but potential damage to macular structure and function were found. Trial registration Retrospectively registered on 09/24/2019 on ClinicalTrials.gov with an ID of NCT04139811.

BACKGROUND AND OBJECTIVE: To study the anatomical and functional outcomes of using epimacular amniotic membrane graft (AMG) to close myopic macular holes (MMHs) in patients with recurrent retinal detachment (RD). PATIENTS AND METHODS: Fourteen patients with recurrent MMH-RD were enrolled in a single-arm, prospective study. Pars plana vitrectomy with peeling of any residual internal limiting membrane, preserved AMG was placed over the macular hole (MH) after air-fluid exchange, all patient left on 16% of C ₂ F ₆ . RESULTS: Fourteen patients (11 females and three males) with an average age of 58.7 years were included; follow-up was 6 months. Thirteen patients (93%) showed retinal reattachment and closure of the hole confirmed by optical coherent tomography. The mean logMAR of best-corrected visual acuity improved to 1.38 compared to 2.2 preoperatively ( P < .002, paired t -test), with no serious intraoperative or postoperative complications. CONCLUSION: Epimacular AMG for MMH-RD is a safe and effective treatment for closure of myopic MHs. [ Ophthalmic Surg Lasers Imaging Retina. 2020;51:101–108.]

Purpose: The purpose of this study is to compare anatomical and visual outcomes after using silicone oil (SO) or C ₃F ₈ gas as tamponades after pars plana vitrectomy (PPV) for retinal detachment (RD) associated with giant retinal tears (GRTs). Methods: A retrospective chart review was conducted for cases that underwent PPV for GRT-associated RD. We excluded eyes that had prior vitreoretinal surgery, a history of ocular trauma or worse than grade B proliferative vitreoretinopathy (PVR). Baseline demographic and ocular characteristics, surgical details and postoperative anatomical and visual outcomes were recorded and statistically analyzed. Results: We included 88 eyes; 48 eyes had C ₃F ₈ gas and 40 eyes had SO as a tamponading agent. Mean age was 39 years. All eyes underwent 23G PPV with no adjuvant scleral buckling and phacovitrectomy was performed for all phakic eyes. Final retinal reattachment was achieved in 86 eyes (97.7%). One eye from each group had recurrent RD. Postoperative vision was significantly better in the gas group (p= 0.008). Prolonged increase of IOP developed in 6 eyes in the SO group and 5 eyes in the gas group. Prolonged uveitis developed in 4 eyes in the gas group and 6 eyes in the oil group (P= 0.04). Epiretinal membranes (ERM) developed in 10 eyes in the gas group and 9 eyes in the oil group. We found no significant difference between both groups regarding postoperative glaucoma or ERM formation. Conclusion: Both agents achieved similar favorable anatomical outcomes in a series of eyes with fresh GRT-associated RD and low-grade PVR, with better visual outcome and less frequent uveitis associated with the use of gas tamponade.

Purpose. To evaluate a new technique of posterior capsulorhexis using air support to treat primary posterior capsular opacification (PCO) during cataract extraction surgery or to prevent postoperative PCO. Setting. (1) Ophthalmology department, Faculty of Medicine, Minia University, 61519, El-Minia, Egypt. (2) Security Forces Hospital, Ophthalmology Department, Riyadh, Kingdom of Saudi Arabia. Design. Prospective, randomized, consecutive case comparative non controlled study. Methods. One hundred eyes of 100 patients with a mean age of 63.3 years with dense cataract were enrolled in the study. Fifty of them (group (1)) were with primary PCO (discovered during the operations) and fifty (group (2)) with clear posterior capsule. All of the patients underwent phacoemulsification and posterior capsulorhexis using the air to support the posterior capsule. Then, IOL implantations were done between the anterior and posterior capsular rims. Postoperatively, each patient was evaluated for the following: visual acuity (UCVA and BCVA), manifest refractive spherical equivalent (MRSE), intraocular pressure, intraocular lens (IOL) stability, visual axis opacification, and posterior segment complications as retinal breaks, retinal detachment, or cystoid macular edema (CME). Results. There were no significant differences in UCVA, BCVA, and MRSE. All cases had a clear visual axis, with stable IOL and normal IOP during the follow-up period without posterior segment complications. The VA improved significantly throughout the follow-up periods in both groups without significant clinical difference. Conclusion. Pneumatic posterior capsulorhexis is a new effective technique for the treatment of primary PCO in dense cataract and for prevention of postoperative PCO with the good visual outcomes and minimal complications. This trial is registered with NCT04007965.

With advances in refractive surgery and demand for cataract removal and lens replacement, the ocular use of nonsteroidal anti‐inflammatory drugs (NSAIDs) has increased. One of the most commonly used NSAIDs is diclofenac (Diclo). In this study, cyclodextrins (CDs), α‐, β‐, γ‐, and HP‐β‐CDs, were investigated with in vitro irritation and in vivo ulceration models in rabbits to reduce Diclo toxicity. Diclo‐, α‐, β‐, γ‐, and HP‐β‐CD inclusion complexes were prepared and characterized and Diclo‐CD complexes were evaluated for corneal permeation, red blood cell (RBCs) haemolysis, corneal opacity/permeability, and toxicity. Guest‐ (Diclo‐) host (CD) solid inclusion complexes were formed only with β‐, γ‐, and HP‐β‐CDs. Amphipathic properties for Diclo were recorded and this surfactant‐like functionality might contribute to the unwanted effects of Diclo on the surface of the eye. Contact angle and spreading coefficients were used to assess Diclo‐CDs in solution. Reduction of ocular toxicity 3‐fold to16‐fold and comparable corneal permeability to free Diclo were recorded only with Diclo‐γ‐CD and Diclo‐HP‐β‐CD complexes. These two complexes showed faster healing rates without scar formation compared with exposure to the Diclo solution and to untreated groups. This study also highlighted that Diclo‐γ‐CD and Diclo‐HP‐β‐CD demonstrated fast healing without scar formation.