Retinal evaluation by fundus angiography before and after vitrectomy and foreign body removal in a patient with ocular siderosis: a case report.

Background: Ocular siderosis (OS) is a rare severe complication arising from retained iron-containing intraocular foreign bodies. In the young male patient reported in this paper, the intraretinal diffusion and distribution of siderotic particles before and after the removal of the foreign body were observed via fundus angiography (FA). Case Description: A 33-year-old decoration worker was diagnosed as the absolute stage of right eye glaucoma in the local hospital and was treated with cataprolol and brinzolamide eye liquid to reduce intraocular pressure. The symptoms did not improve. He came to our hospital for treatment. He was finally diagnosed with "foreign body, siderosis, and secondary glaucoma in the right eye" based on eye examinations. According to the observation via fundus fluorescein angiography (FFA), indocyanine green angiography (ICGA), grade 2-3 vascular occlusion extended in a gradient along the foreign body, there was no retinal perfusion in the temporal retina, the siderotic particles were distributed along the artery, and inflammatory changes occurred in the optic nerve and retinal vein. He underwent pars plana vitrectomy, foreign body removal, retinal laser photocoagulation, silicone oil filling and pressure reducing valve implantation. Silicone oil was removed three months later. The postoperative visual acuity was not improved, the intraocular pressure was well controlled, and there was concurrent cataract, but it did not affect the fundus examination. At 3 and 10 months after operation, the fundus angiography showed that the particles distributed along the artery decreased, the inflammation of optic nerve and retinal vein subsided, and the laser spots in the non perfusion area were clear. Conclusions: The influence of iron ion on retinal vein and the distribution of iron ion along retinal artery can be seen macroscopically by FA before and after foreign body removal.

Ocular siderosis: a misdiagnosed cause of visual loss due to ferrous intraocular foreign bodies-epidemiology, pathogenesis, clinical signs, imaging and available treatment options.

PURPOSE: The purpose of this paper is to provide a meaningful literature review about the epidemiology, pathogenesis, clinical signs, imaging and treatment of ocular siderosis (OS). METHODS: A computerized search from inception up to March 2020 of the online electronic database PubMed was performed using the following search strings: "ocular siderosis" and "siderosis bulbi". The reference list in each article was analysed for additional relevant publications. RESULTS: OS is an uncommon cause of visual loss due to a retained ferrous intraocular foreign body (IOFB). It may develop from 18 days to years after a penetrating trauma that usually occurs during hammering. On average, patients are 22-25 years old, and the vast majority are male. The most common cause of OS development is delayed presentation by the patient or missed diagnosis of IOFB after trauma. The pathophysiology is not fully understood; nevertheless, iron deposition causes hydroxyl radical formation, which damages photoreceptors and retinal pigment epithelium. Moreover, iron damages retinal vessels with consequent inner retinal layers degeneration. The most frequent signs are iris heterochromia, pupillary mydriasis, cataract development and retinal arteriolar narrowing with pigmentary retinal degeneration. Electroretinogram signs, in particular, b-wave amplitude reduction, arise earlier than clinical signs. Orbital CT scans and ultrasonography play an essential role in detecting IOFBs. Treatment depends on the IOFB location and OS development. However, it is crucial to remove the IOFB after OS development because visual acuity and clinical signs may improve. Anterior segment IOFBs can be dislodged using an intraocular magnet (IOM) or forceps through limbal paracentesis. In contrast, posterior segment IOFBs require a pars plana vitrectomy and IOM or forceps to be removed through an enlarged sclerotomy or the limbus. CONCLUSION: Recommending the usage of protective glasses and spreading knowledge about OS may further benefit patient care.

Siderotic glaucoma without detectable intraocular foreign body in a pseudophakic eye: a case report.

BACKGROUND: Ocular siderosis is induced by a retained intraocular foreign body (IOFB) containing iron and can present as siderotic glaucoma. We report a rare case of histopathologically proven siderotic glaucoma in a middle-aged blacksmith with a preceding history of ocular trauma but no radiologically detectable IOFB. CASE PRESENTATION: A 42-year-old blacksmith presented with an elevation of intraocular pressure (IOP) in left eye showing iris heterochromia and brownish deposits throughout the trabecular meshwork (TM). Preoperative ophthalmic examination did not reveal any retained IOFBs. Electroretinography showed the classic changes of retinal degeneration in ocular siderosis. Histopathologic staining of the TM verified the presence of iron deposits. CONCLUSION: This case underlines the importance of the close monitoring of patients with a history of ocular trauma and highlights the necessity of electroretinography, histopathologic study, and detailed ophthalmic examination in the diagnosis of siderotic glaucoma, even if there is no definite radiologically detectable IOFB.

Ocular Siderosis Secondary to Retained Intraocular Foreign Body: A Case Report.

Intraocular foreign bodies (IOFBs) can present in an insidious manner. A 20-year-old male presented with gradual visual loss in the right eye over a six-month period. He was found to have a dense cataract. During examination he was noted to have a small, healed corneal scar and subtle iris heterochromia. Further questioning revealed a previously undisclosed metal-on-metal hammering injury concerning for an IOFB. B-scan ultrasonography was inconclusive and CT studies confirmed the presence of IOFB. The patient underwent a combined cataract extraction with intraocular lens implantation with a pars plan vitrectomy, removal of IOFB, and endolaser. He had an excellent visual outcome, despite developing siderosis. A high index of suspicion should be raised for any asymmetric cataract formation, especially in younger patients. Careful examination for findings such as healed corneal scars or iris heterochromia may aid in diagnosing previously undisclosed injuries.

Electrophysiological findings in delayed discovery of a metallic intraocular foreign body in a child: case report.

PURPOSE: To report a case of a child with strabismus and delayed discovery of a metallic intraocular foreign body with good recovery of visual acuity and stereopsis with 36-month follow-up. METHODS: A 4-year-old girl was evaluated due to exotropia of right eye initiated 9 months before with progressive worsening. Visual acuity was 1.00 logMAR (20/200) in the right eye and 0.00 logMAR (20/20) in the left eye. Anterior segment evidenced a small paracentral corneal leukoma, posterior synechia and mild lens opacity in the temporal quadrant only in the right eye. Fundus examination in the right eye identified the presence of an intraocular foreign body, with appearance of metallic components surrounded by retinal pigmented endothelial cells atrophy. Full-field electroretinography (ERG) showed reduced amplitudes and delayed implicit times for both rods and cones in the affected eye. All tests were normal in the fellow eye. RESULTS: Pars plana vitrectomy was promptly performed in the right eye, followed by phacoemulsification with intraocular lens implantation 4 months later due to worsening of the lens opacification. The full-field ERG was repeated after the surgical procedures. The ERG showed mild worsening of all responses in the right eye. After 36 months of follow-up, visual acuity was 0.20 logMAR (20/32) with improvement of the ocular misalignment and with 60 s of arc stereopsis with ERG responses unchanged. CONCLUSION: In this young girl perforating ocular trauma with metallic material was lately diagnosed with strabismus as a sign of alert. Prompt surgical intervention and proper management were essential to provide reasonable visual function including some degree of stereopsis, even though retinal dysfunction characterized by ERG was persistent.

[Intraocular ferritin production due to an iron-containing intraocular foreign body]. / Synthèse intraoculaire de ferritine suite à un corps étranger intraoculaire ferrique.

INTRODUCTION: Ocular siderosis is a rare but severe complication of open globe trauma with intraocular retention of a metallic foreign body. CASE STUDY: We report a case of recurrent uveitis in a 37-year-old patient. The ophthalmic examination revealed poor vision in the left eye, lid edema, limbal scleromalacia, hyphema and severe ocular hypertension. Orbital CT showed the presence of a radio-opaque IOFB between the crystalline lens and vitreous body. An aqueous humor sample was obtained for iron and ferritin levels. The results came back 100 and 2000 times higher, respectively, than the serum reference values. DISCUSSION: The very high iron content is the result of a sustained release from the metallic INFB and is responsible for ocular siderosis in our patient. The extremely high ferritin level would be the result of in situ synthesis by the various cells of the ocular structures in order to preserve the components of the eye. Measurement of these two levels would improve the diagnosis, prognosis and treatment of metallic IOFBs.

Siderotic cataract with no signs of intraocular foreign body.

BACKGROUND: Ocular siderosis is a clinical condition induced by deposition of an iron-containing intraocular foreign body. We report a unique case of histopathologically proven lens siderosis in a young woman with a preceding history of trauma but no signs of retained intraocular foreign body. CASE PRESENTATION: A 32-year-old woman presented with an opacified lens showing brownish deposits on the anterior capsule and underwent cataract surgery. Preoperative ophthalmic examination did not show any retained intraocular foreign body. Histopathologic staining of the anterior capsule confirmed the presence of iron deposits and macrophages. Electroretinography examination performed in the postoperative period showed the changes characteristic of retinal degeneration in ocular siderosis. CONCLUSION: This case illustrates the importance of close monitoring of patients with a history of trauma or previous penetrating injury to the eye, even if there is no intraocular foreign body, because they might develop ocular siderosis at a later stage. This case report underscores the importance of electroretinography and histopathologic analysis, in addition to ophthalmic examination, in the diagnosis of ocular siderosis.

An animal model (guinea pig) of ocular siderosis: histopathology, pharmacology, and electrophysiology.

PURPOSE: Ocular siderosis is a rare sight-threatening complication that occurs after a penetrating ocular injury by an iron-containing foreign body. The purposes of this study were to (i) investigate the histopathology, electrophysiology and iron levels/accumulation in ocular siderosis using an animal (Guinea pig) model and (ii) determine the appropriate timing for follow-up foreign body-removal surgery. MATERIALS AND METHODS: Thirty guinea pigs were divided into five groups (n = 6 animals/group). On day-1, an iron body was inserted into the vitreous of the right eye of all animals; the left eyes were left undisturbed and were used as controls. At the end of each week during the 5-week study period, electroretinography (ERG) was performed on all animals in one of the five groups. Each animal in that group was sacrificed, after which both eyes were enucleated for histopathological and pharmacological evaluation of intraocular iron. RESULTS: Accumulated iron levels of study eyes were significantly higher than those of control eyes (135.13 and 13.55 µg/g, respectively, p < 0.01). In addition, there was a significant decrease in electrophysiological responses of study eyes. During the first week, iron levels were higher in study eyes than control eyes, but neither histological iron accumulation nor decreased electrophysiological responses could be detected. By the end of the second week, increased iron accumulation was observed histologically in intraocular tissues, along with signs of retinal toxicity, as verified by decreased electrophysiological responses. CONCLUSIONS: The present study indicates that the 14th day after a penetrating eye injury by an iron-containing intraocular foreign body represents a clinically critical threshold, after which structural damage to and functional alterations in ocular tissues occur.

Application of Prussian blue staining in the diagnosis of ocular siderosis.

AIM: To explore the value of Prussian blue staining in the diagnosis of ocular siderosis. METHODS: Between January 2012 and January 2013, the Prussian blue stain used in anterior lens capsule and vitreous liquid after centrifugation from patients with definitive diagnosis and suspicious diagnosed of ocular siderosis. At the same time, give a negative control. RESULTS: Anterior lens capsule membrane and liquid of vitreous cavity from patients with definitive diagnosis and suspicious diagnosed of ocular siderosis revealed ferric ions that stained positively with Prussian blue. In the control group, there is no positive reaction. CONCLUSION: Prussian blue staining in the diagnosis of ocular siderosis has a very significant worth, suspected cases can be definitive diagnosed.