Occult intraocular aluminium foreign body causing rhegmatogenous retinal detachment: a case report

BACKGROUND: Ocular trauma is complex and varied, and some occult intraocular foreign bodies (IOFBs) can lead to uncommon symptoms and signs. We report a case of rhegmatogenous retinal detachment (no obvious wound, no pain, no intraocular infection or other symptoms) caused by an occult intraocular aluminium foreign body, which could have been easily missed. CASE PRESENTATION: A 42-year-old male presented to the outpatient department of our hospital complaining of fluttering black dots and decreased vision in his left eye that began 3 months earlier. He was diagnosed with "floaters" at a community hospital. He denied a history of ocular trauma or previous surgery. The cornea and lens of the left eye were clear. A small patch of pigmentation was noted in the temporal sclera. Fundoscopy revealed macula-off retinal detachment. After mydriasis, elliptical holes were seen in the peripheral retina at 2:30, and a suspicious hyperreflective strip was found under the anterior lip of the retina by Goldmann three-mirror contact lens examination; the strip was confirmed to be an IOFB by orbital CT. The IOFB was removed through pars plana vitrectomy without any complications. CONCLUSION: Unlike iron and copper IOFBs, aluminium IOFBs are more inert and more likely to be missed. For people with special occupations (construction workers, mechanics, etc.), when abnormal pigmentation of the sclera is found, the possibility of foreign bodies in the eye should be considered. In the process of disease diagnosis and treatment, it is necessary to ask for a detailed history, including occupation history and practice, and perform careful physical and targeted examinations. Such comprehensive analysis regarding the above information will minimize the chance of missed diagnosis.Awareness of occult IOFB in high risk occupations and prompt referral to a retinal surgeon is of outmost importance.