Ophthalmic Complications of Dermatomyositis

The heliotrope eyelid eruption is considered as a hallmark of DM. The associated periorbital redness and edema, producing ptosis, chemosis, and exophthalmos may initially be mistaken for infective orbital cellulitis. Ocular muscles in DM remain normal, even in advanced, untreated cases. If the ocular muscles are affected, the diagnosis of inflammatory myopathy should be in doubt [1], and the diagnosis of orbital myositis should be discussed [2]. Involvement of the extraocular muscles is extremely rare, and can cause pain and ophthalmoplegia [3]. Ptosis of the eyelids, diplopia, and strabismus due to extraocular muscle involvement can be observed in some DM patients [4].

Ocular manifestations have included conjunctival edema, nystagmus, extraocular muscle imbalance, iritis, cotton wool spots, optic atrophy, and conjunctival pseudopolyposis [5, 6]. Eyelid and lens abnormalities are frequently observed in patients with JDM, while retinopathy is rare [7]. The bulbar conjunctiva shows areas with dilated vessels and areas that look white and avascular [8]. In addition, vasculitis involving the conjunctival vessels can produce infarction. Additional features seen in DM are iritis [9], episcleritis [10], and uveitis with glaucoma [11]. Thromboses of the vessels at the margin of the eyelid have been detected in juvenile DM patients. Also, as a reflection of the vasculopathy these patients may develop transient “cotton wool“ spots in the retina [12]. The cotton wool spots are nonspecific and indicate arteriolar obstruction or capillary damage, mediated by nerve fiber layer infarction, which produces axonal swelling and rupture [13]. Retinopathy associated with DM is initially described by Bruce [14] in 1938. Later, a few cases and studies have been reported in both adults and children [7, 15–19]. Retinopathy, leading to persistent and profound visual loss, has also been reported [17, 20–22]. More commonly, retinopathy associated with DM completely resolves without lasting complications [13] or with the development of retinal neovascularization [19]. Rarely, areas of pigment clumping are left, some surrounded with lighter halos (Elschnig's spots) indicating choriocapillary infarction [21]. Later still, there may be diffuse pallor of the optic disc resulting from retinal neuronal atrophy, producing irreversible visual impairment, which is very rare [21]. It has been postulated that children are more likely to have associated retinopathy because of the increased systemic vasculitis seen in juvenile DM [23]. Profound visual loss in DM is caused by macular hemorrhage or macular edema, which produces central scotomas. Visual recovery is usually complete [24, 25]. Over subsequent months the hemorrhages and cotton wool spots will be expected to resolve completely. The retinal infarctive events are felt to be similar to the arteriolar endothelial damage and platelet thrombi seen in muscle biopsy specimens [26].