Intraocular injections

Bhattacherjee, P. and Henderson, B. (1987). Inflammatory responses to intraocularly injected interleukin 1. Curr. Eye Res. 6, 929-934. 

FDA approved intraocular injections include mio-tics, viscoelastics, and viscoadherents and an antiviral agent for intravitreal injection. The approved intraocular miotics, carbachol (Miostat ) and acetylcholine (Miochol ), are injected into the anterior chamber at the end of cataract surgery to constrict the pupil and allow the iris to cover the implanted intraocular lens. Carbachol is formulated in a BSS vehicle in sterile water for injection at a physiological pH... 

Contraindications Direct intraocular injection, historyof clinically severe hypersensitivity to probenecid or other sulfa-containing drugs, renal function impairment (se-... 

Nevertheless, very limited research has been carried out to develop DDS for the posterior segment of the eye in the last decades. Whereas new antiangiogenic compounds and neurotrophic factors can open new therapeutic avenues in the treatment of AMD, retinal dystrophies and ocular manifestations of diabetes, the frequent intraocular injections of these compounds remain a problem and are associated with complications and discomfort for the patient. Thus, the need for efficient noninvasive DDS for the administration of drugs to the back of the eye is awaiting a ground-breaking multidiscipline advancement. 

Low-dose regimens frequently result in very low corticosteroid concentrations in body fluids (e.g., low pg/mL range in plasma). PK analysis that is often necessary to manage these therapies is hindered by the inadequate sensitivity by most established analytical methods. In addition, certain drug delivery strategies, such as inhalation or intraocular injection, result in systemic levels too low to be detected by current methods. Furthermore, administration of some corticosteroid prodrugs, such as these in the forms of acetates/propionate, often results in sustained, low concentrations in plasma. Therefore, a highly sensitive and selective analytical approach is necessary for cases in which sustained low concentration of corticosteroids may be present systemically or in tissues. 

Occasional development of Probable development of some adrenal adrenal suppression suppression Aggravation of a dendritic ulcer Discomfort with injection White residue possible Occasional white material, which is Epithelial keratopathy from cosmetically objectionable frequent applications Subconjunctival adhesions Occasional conjunctival infections Allergy to diluent Occasional orbital infection Occasional intraocular injection of steroid Ulceration of conjunctiva after repeated injections if not given behind the eye Exophthalmos and rugae in fundus Papilledema Adrenal suppression Occurrence of systemic side effects more likely... 

There is a preponderance of evidence that the incidence of postoperative endophthalmitis is reduced when antiseptics (povidone iodine) and antibiotics are used preoperatively.The use of balanced salt solution, to which an antibiotic has been added, to irrigate the eye during surgery is advocated by some but tempered by concerns of intraocular toxicity and questions of efficacy. Sub-Tenon s capsule injection of an antibiotic just before surgery or subconjunctival injection of antibiotic at the end of the surgery is also used to prevent infection, but risk of inadvertent intraocular injections resulting in retinal antibiotic toxicity must be considered. In addition, oral antibiotics may be used at the time of surgery and 1 day postoperatively as a prophylactic measure. 

Complications from retrobulbar block can arise from accidental scleral perforation and intraocular injection of local anesthetic. 

Topical instillation 218 Periocular injections 220 Intraocular injections 220 Parenteral administration 220 Innovative drug delivery systems 221... 

All intraocular injections should be carried out imder general anesthesia. 

Because of its multiple effects on immunoinflammatory response, recombinant IL-12 has been shown to have therapeutic activity in a variety of mouse tumor and infectious disease models and is being evaluated in clinical trials in human cancer patients. IL-12 also appears to play a role in the genesis of some forms of immunopathology, including endotoxin-induced shock and some autoimmune diseases associated with aberrant Thl activity. Therefore IL-12 antagonists may also have therapeutic potential in the treatment of autoimmune disorders. In addition, intraocular injection of IL-12 significantly inhibited the development of endotoxin-induced intraocular inflammation, suggesting that IL-... 

The FDA approved intraocular injections include miotics, triamcinolone acetonide, pegaptanib sodium, ranibizumab, formivirsen sodium, viscoelastics and viscoadherents, and an antiviral agent for intravitreal injection. There are many small and large molecules currently in clinical trials that are delivered via intravitreal injection for the treatment of a variety of retinal diseases with a large area of focus on the treatment of AMD and macular edema. 

Nakamichi N, Chidlow G, Osborne NN. 2003. Effects of intraocular injection of a low concentration of zinc on the rat retina. Neuropharmacology 45 637-648. 

Periocular injections, subconjunctival, subtenons, and retrobulbar injection of drugs have been frequently investigated as a means to increase ocular availability. Subtenon injections of steroids, such as triamcinolone acetonide, are frequently used to control inflammatory conditions of the posterior segment such as cystoid macular edema, although this delivery route carries a risk of inadvertent intraocular injection (45). 

Lincoff H, Zweifach P, Brodie S, et al. Intraocular injection of lidocaine. Ophthalmology 1985 92 1587-1591. 

Hodge WG, Lalonde RG, Sampalis J, Deschenes J. Once weekly intraocular injections of ganciclovir for maintenance therapy of cytomegalovirus retinitis clinical and ocular outcome. J Infect Dis 1996 174 393-396. 

The half-life of vancomycin following intraocular injection is long, and ranges from 25.5 to 56 hours (14,15). Removal of the lens dramatically decreases the half-life to 9.8 hours (14). In inflamed eyes the half-life is slightly longer in the phakic eye and is slightly shorter in a model of infection (14,15). 

In two studies, samples were obtained from the vitreous cavity after intraocular injection. Ferencz (43) identified a range of 25-182 pg 44-72 hours after injection. Gan (44) identified average levels of 10.3 pg/mL three days after injection. Rough estimates indicate this is consistent with the half-life of 24 hours as suggested by data in the rabbit (44). 

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