1. Siderosis Bulbi Zamzam Al-baker,MD Consultant Opthalmology
Ophthalmology depart./Hamad
Medical Corporation-Qatar

2. Ocular History 10 year old boy .
January /2005: OS: recurrent redness and photophobia for 9 months , improved after topical steroids
gradual decreased vision since 3 months
he remembered a trivial non-specific ocular trauma 12 months back.

3. Ocular History Systemic review and medical check up: unremarkable
Laboratory blood investigations and systemic uveitis work-up : normal

4. December 2005 - First Presentation
VA: OD 20/20, OS 20/400 .
IOP:OD 14 mmHg, OS 6 mmHg.
OD: anterior and posterior segment no cells
OS:
Conjunctiva: mild cilary injection .
Cornea : diffuse stromal haze and brown discoloration with white large keratic precipitates inferior

5. First Presentation A/C: deep, 3 + cells.
Pupil: 6mm, round with multiple areas of posterior synechia, on dilatation with multiple brown-rusty deposits on anterior lens capsule.
Lens: 3+ nuclear & PSCC cataract
Vitreous: 2+ Vitreous haze
Fundus: hazy view, scattered RPE clumping, pigmented shadow at inferior temporal quadrant

6. Rusty brown deposits on anterior lens capsule

7. First Presentation - Ultrasound
Vitreous opacities with small foreign body on the retina with posterior shadow effect

8. Further Investigations
ERG: patient was not cooperative
CT scan orbit: no foreign body seen

9. Masquerading as Panuveitis
Diagnosis
Siderosis Bulbi
Masquerading as Panuveitis

10. Treatment – Follow up December- 2006
anterior granulomatous reaction was controlled with topical steroids drops
January-2006
OD phacoemulsification + parsplana vitrectomy + removal of intraocular foreign body +intraocular lens implant + silicon oil tamponade

11. Follow-up – June 2006
VA: 20/400
cornea: stromal haze and brown deposits
A/C: clear
pale optic disc
generalized RPE clumbing, flat retina centrally under silicone oil
inferior tractional detachment with subretinal fibrosis
Patient did not attend for further follow up

12. Conclusion
Metallic FB are electrolytically dissociated or react with the tissue-fluid to form decomposition product, usually by oxidation and cause specific toxic reaction such as siderosis or chalosis.
The clinical manifestations of ocular siderosis result from a chronic degenerative process presumably induced by the oxidation of reduced forms of elemental iron that result in the libration of toxic oxidants can mimic multiple other uveitis disorders

13. Clinical Manifestations of ocular Siderosis
Rust-colored corneal stroma
Iris heterochromia (affected side is darker)
Pupillary mydriasis
Chronic uveitis
rust-colored anterior subcapsular deposits
Cataract
Lens sub-luxation
Secondary glaucoma
Retinal pigmentary changes.

14. Diagnosis of Ocular Siderosis
suspicion
detailed history
complete ocular examination
gonioscopy
X-ray , CT scan
US, ERG, EOG

15. Comments
In this case the presence of unilateral granulomatous panuveitis in such age alerted us to the possibility of masquerade.
There were other anterior segment signs typical for ocular siderosis, like the rusty corneal stromal haze, and the brown rustic anterior subcapsular deposits .

16. Conclusion
Siderosis seems to be more advanced when the foreign body is located in the posterior segment.
Foreign bodies tend to be better tolerated when located in the anterior chamber or imbedded in the lens.

17. Conclusion The natural course of a retained IOFB varies
small IOFBs may be completely resorbed, the FB may become encapsulated
the siderotic changes may stabilize or regress
the FB may lose its magnetic properties or become radiolucent to X-rays
or progressive siderotic changes may occur.

18. Conclusion
Siderotic changes have been reported to occur from 18 days to 8 years after the injury
The VA at presentation is an indicator for the final VA in severe forms of siderosis
Hypotony and retinal pigment changes are signs of advanced severe cases of ocular siderosis