DISCUSSION
Bilateral conjunctival and scleral necrosis after sub-Tenon
triamcinolone injection is a rare but severe complication, especially in
children. This 3-year-old boy’s case underscores the danger of local
steroid-induced tissue necrosis, an experience well described in adult
cases but infrequently in children. The mechanisms likely include direct
cytotoxicity of triamcinolone and its preservatives, especially benzyl
alcohol, which has been associated with ocular surface toxicity and
delayed wound healing (1, 9).
Moreover, steroid-induced vasoconstriction could have potentiated
ischemic necrosis in the supronasal quadrants areas with relatively poor
vascular density (6,10).The patient in this instance had localized
conjunctival ischemia and thinning of the sclera at the site of
injection, which indicates a local toxic effect of the drug on ocular
tissue. Experimental studies have indicated that benzyl alcohol
initiates disruption of the epithelial cell membrane and apoptosis,
which results in delayed healing and inflammation of the wound (9).
A similar case has been reported in a child with conjunctival necrosis
after subconjunctival injection of triamcinolone acetonide for chronic
severe anterior uveitis (8). In a similar case, another case had been
reported where there was chronic retention of steroid resulting in
progressive thinning of the sclera(6).
In contrast to these cases, our patient had neither systemic risk
factors nor previous surgery, pointing towards drug toxicity as the
etiology. In addition, though most of the adult cases need grafting,
early treatment with drug withdrawal, surgical debridement, and support
therapy permitted spontaneous healing without grafting, highlighting the
possible conservative management in children with minor necrosis.
This case reminds us that one must remain vigilant while using
periocular steroids in children because of the tremendous susceptibility
of their tissues and prolonged drug retention in the developing eye.
Practitioners must be alert for any early signs of conjunctival ischemia
following the injection, which could be instrumental in preventing
dangerous scleral thinning and structural complications. Lack of
pediatric data for steroid-induced ocular necrosis, further research is
needed to determine risk factors, better delineate steroid injection
techniques, and investigate alternatives to safer control of
postoperative inflammation.