Confocal microscopy in ocular argyrosis

Multimodal ocular imaging in diagnosis and management of occupational ocular argyrosis

Occupational ocular argyrosis is a rare disorder associated with accumulation of silver in the eye due to its occupational exposure. A 39-year-old male patient, a silver utensils polisher for the past 30 years, presented with bilateral gradual diminution of vision (presently 20/200) for 2 years. His serum silver levels were raised and ocular examination revealed bilateral greenish brown corneal deposits and complicated cataract. Anterior segment optical coherence tomography (OCT) and confocal microscopy suggested deposition of silver in various corneal layers. Multifocal electroretinogram showed a generalized decrease in sensitivity of P1 waves. Increased internal aberrations on aberrometric profile favoured phacoemulsification followed by intraocular lens implantation in both eyes. Postoperatively, the visual gain of 20/20 and normal fundus picture on indirect ophthalmoscopy, macular OCT, and fundus autofluorescence favored good prognosis in both eyes.

Clinical and Forensic Aspects of the Different Subtypes of Argyria

Argyria encompasses the different cosmetic alterations that can develop if enough silver particles deposit in a specific tissue, typically in the skin, ranging from localized dark-blue macules to a generalized slate-gray/bluish tinge following systemic absorption. This work aims to fully review the state of the art regarding pathophysiology, diagnosis, treatment, and relevant clinical and forensic features of argyria. Argyria has been diagnosed in a wide range of ages, both sexes and varied ethnicities, with no known individual predisposing factors. Ultraviolet radiation with subsequence increases of melanin production aggravates the discoloration due to a reduction in the silver deposits. Physical examination and silver exposure in the anamnesis can be highly suggestive of the diagnosis, but a histopathological analysis with Energy-Dispersive X-ray Spectroscopy is required to unequivocally determine the discoloration etiology. Safe and effective treatment has only been accomplished with laser techniques, though only a few cases have been reported and with limited follow-up time. In conclusion, argyria typically has an occupational or iatrogenic etiology. It should be suspected when a patient presents with typical skin or eye lesions. A seemingly viable treatment modality, with laser technology, is finally within the horizon.

[Bluish-gray discoloration of skin and conjunctiva]

Colloidal silver used as a suspension for (alternative) therapeutic purposes or silver exposure due to environmental or working conditions can lead to irreversible deposits of silver granules in the skin (bluish-gray hue of the skin), mucosa, cornea, retina and internal organs. Silver-induced discoloration of the conjunctiva should therefore be taken into account when a bluish-gray discoloration raises the suspicion of conjunctival melanoma.

Case Report: In Vivo Confocal Microscopic Appearance of Corneal Argyrosis

SIGNIFICANCE

This report details the natural history of corneal argyrosis over 3 years using in vivo confocal microscopy to document regression of hyperreflective deposits, as well as effects on corneal nerves and endothelial cell morphology.

PURPOSE

To report the in vivo confocal microscopic features and clinical characteristics of a case of bilateral corneal argyrosis.

CASE REPORT

A 52-year-old man referred to us 3 months following cautery of the palpebral conjunctiva of both eyes with a silver nitrate stick was observed over the course of 3 years, during which slit-lamp photography and in vivo confocal microscopy were performed. At the first visit, slit-lamp examination showed a light blue-green discoloration and a thick, yellow, oval discoloration in the right and left cornea, respectively. One year later, under slit-lamp examination, the right cornea appeared nearly transparent, and the discoloration in the left cornea had remarkably regressed. In vivo confocal microscopy done at that time showed highly reflective deposits in Descemet membrane of the right cornea and throughout Bowman layer, the stroma, and Descemet membrane of the left cornea. Three years later, no accumulation of silver was observed during slit-lamp examination of either eye. In vivo confocal microscopy of the right cornea did not reveal any silver deposits, and the corneal structure appeared normal. In the left cornea, some silver deposits were still evident in Descemet membrane, and alterations of corneal nerve and endothelial cell morphology were also evident.

CONCLUSIONS

This report reviews the 3-year natural history of a patient with corneal argyrosis. In vivo confocal microscopy demonstrates that over time the corneal argyrosis gradually resolves without any treatment. However, the presence of silver in the cornea may impact the corneal nerves and endothelial cells.

Diagnostic methods in ocular argyrosis: case report

Purpose

The aim of this report is to present a case of a patient, metal foundry worker, who had been exposed to industrial silver salts for over 20 years. It is well established that chronic exposure to silver compounds can cause accumulation of silver deposits in various tissues. This condition is referred to as argyrosis or argyria, whereas changes related to eye tissues are defined as ocular argyrosis.

Methods

A complete eye examination, corneal confocal microscopy, kinetic and static visual field test, posterior segment optical coherent tomography, pattern visual evoked potentials (PVEP), flash visual evoked potentials, multifocal electroretinogram, pattern electroretinogram (PERG), full-field electroretinography (FERG) and electrooculogram were all performed.

Results

Eye examination revealed decreased visual acuity, corneal deposits and drusenoid changes within the macula. Although electrophysiology tests did not show changes in the function of retinal pigment epithelium, they revealed abnormal function of photoreceptors in the central and peripheral retina. PERG abnormalities and delayed latency of P100 wave in PVEP confirmed impaired function of the inner layers of the retina in the macular region.

Conclusions

Corneal confocal microscopy and electrophysiological tests may help confirm the diagnosis of ocular argyrosis.

In vivo reflectance confocal microscopy characterization of silver deposits in localized cutaneous argyria

Localized cutaneous argyria is a rare condition secondary to skin deposition of silver following exposure to substances containing this metal. The clinical appearance and dermoscopy findings require deep melanocytic lesions and particularly melanoma metastasis to be ruled out. Silver deposits are usually confirmed by scanning electron microscopy and/or energy-dispersive X-ray spectroscopy. Herein we describe the in vivo reflectance confocal microscopy (RCM) features observed in one case of localized cutaneous argyria. These features include the presence of a hyperrefractile network in the papillary dermis and a periadnexal dotted bright pattern. In vivo RCM might be a useful tool for an early diagnosis of this uncommon entity.

Confocal microscopy in biopsy proven argyrosis

Purpose. To evaluate the confocal microscopy findings of a 46-year-old male with bilateral biopsy proven argyrosis. Materials and Methods. Besides routine ophthalmologic examination, anterior segment photography and confocal microscopy with cornea Rostoch module attached to HRT II (Heidelberg Engineering GmbH, Heidelberg, Germany) were performed. Findings. Squamous metaplastic changes on conjunctival epithelium and intense highly reflective extracellular punctiform deposits in conjunctival substantia propria were detected. Corneal epithelium was normal. Highly reflective punctiform deposits starting from anterior to mid-stroma and increasing through Descemet's membrane were evident. Corneal endothelium could not be evaluated due to intense stromal deposits. Conclusion. Confocal microscopy not only supports diagnosis in ocular argyrosis, but also demonstrates the intensity of the deposition in these patients.

A Case of Bilateral Descemet's Membrane and Subepithelial Opacity: In vivo Laser Confocal Microscopic Study

Purpose

To report the in vivo laser confocal microscopy findings from a patient with Descemet's membrane and subepithelial opacity OU.

Case Report

A healthy 41-year-old male with Descemet's membrane and subepithelial opacity OU was studied. Routine ophthalmic examination, standard slit-lamp biomicroscopy, and in vivo laser confocal microscopic analysis of the entire corneal layer were performed. Slit-lamp biomicroscopy revealed subepithelial opacity in the mid-peripheral to peripheral cornea and numerous opacities located at the level of Descemet's membrane. It was difficult to distinguish the precise histological location of the opacity. In vivo laser confocal microscopy showed numerous hyperreflective particles in the subepithelium to superficial stroma and hyperreflectivity of Descemet's membrane. No abnormalities could be detected in the epithelial cell layer, midstromal layer, deep stromal layer, or endothelial cell layer.

Conclusion

Although the origin of the corneal opacities was unclear, in vivo laser confocal microscopy was useful for observing microstructural abnormalities in a case of Descemet's membrane and subepithelial opacity.

Ocular argyrosis secondary to long-term ingestion of silver nitrate salts

This case report describes the clinical, autofluorescence, and optical coherent tomography findings in a patient with panocular argyrosis secondary to chronic intake of diluted silver nitrate salts in his water supply. An 86-year-old Caucasian male with a distinctive gray-bluish hue of the skin presented to our clinic, having developed a slow decrease in visual acuity in both eyes and nyctalopia for the past 2 years. Based on the patient’s history of chronic intake of silver nitrate salts and a positive skin biopsy (performed by the dermatology department, data not shown), a diagnosis of panocular argyrosis was made. Fluorescein angiography showed choroidal blockage with a completely dark choroid. Fundus autofluorescence was within normal limits. Optical coherent tomography showed multiple excrescences of retinal pigment epithelium in both eyes. Although the drusen-like changes on fundus examination and retinal pigment epithelium changes may account for the diminished vision, the presence of concomitant nyctalopia suggests underlying damage of the photoreceptors.

Yellow corneal ring associated with vitamin supplementation for age-related macular degeneration

PURPOSE

To report the first described cases of peripheral yellow corneal rings secondary to vitamin supplementation for age-related macular degeneration (ARMD).

DESIGN

Retrospective single-center case series.

PARTICIPANTS

The eyes of 4 patients taking vitamin supplementation for ARMD were examined at the University of Pittsburgh Medical Center Department of Ophthalmology between January 2010 and April 2011.

METHODS

We reviewed the medical records of 4 patients with peripheral corneal rings receiving vitamin supplementation for ARMD.

MAIN OUTCOME MEASURES

The presence of peripheral yellow corneal rings, skin findings, and serum carotene levels.

RESULTS

Each patient had circumferential, yellow, peripheral corneal rings and exhibited subtle yellowing of the skin most notable on the palms. Serum carotene levels were normal in 2 of the 3 patients and markedly elevated in the last patient in whom it was measured.

CONCLUSIONS

It is unclear at this time how to counsel patients with this ocular finding. We suspect that these rings are more common than generally appreciated because they may have a subtle appearance or be misdiagnosed as arcus senilis. We suggest that a formal study be performed on a cohort of patients taking vitamin supplementation for macular degeneration that specifically screens for yellow rings and measures serum carotene levels when they are identified.