Severe silver nitrate injury to the eye

Accelerated corneal collagen cross-linking in clinical management of infectious keratitis

Objective

To evaluate the clinical efficacy of corneal collagen cross-linking (CXL) in the treatment of infectious corneal diseases.

Methods

This study retrospectively analyzed the clinical efficacy of CXL in 65 eyes with infectious keratitis in Jinan Second People’s Hospital from December 2016 to June 2018. During 6 months of follow-up after CXL treatment, the results of confocal microscopy and anterior segment optical coherence tomography, as well as visual acuity and corneal biomechanical parameters, were recorded in detail.

Results

In general, the overall cure rate was 93.85%; no corneal endothelial dysfunction was encountered in any patients. After 6 months of follow-up, the visual acuity of cured patients was significantly enhanced, while corneal thickness was significantly reduced. Hyphae growth of patients with fungal keratitis was completely inhibited at 1 month postoperatively. Furthermore, corneal biomechanical parameters (i.e., central corneal thickness, deformation amplitude, and pachymetry intraocular pressure) were significantly improved after surgery, compared with baseline measurements.

Conclusion

Accelerated CXL may be an effective adjuvant treatment for infectious keratitis.

Corneal injury secondary to silver nitrate stick mistaken for cotton bud

Purpose

This case report highlights the potential for error when removing corneal foreign bodies in a shared speciality area in Accident and Emergency (A&E).

Observations

This case presents the accidental use of a silver nitrate stick rather than a cotton bud to remove a corneal foreign body. This resulted in a corneal injury requiring ophthalmological referral and management with topical antibiotics, topical steroids and lubricants.

Conclusions

Mistaking a silver nitrate stick for a cotton bud is a tangible risk in a busy A&E and can result in significant corneal injury. Clinicians and departments can greatly reduce this risk by having separate and secure storage of similar consumables, as well as keeping consumables in original packaging and discarding of the remainder after a pack has been opened. Minimizing the risk for error will better safeguard and improve patient safety.

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.

Ocular manifestations of monoclonal copper-binding immunoglobulin

The dense accumulation of copper in Descemet membrane and lens capsule is the characteristic manifestation of a circulating monoclonal antibody with strong affinity for copper. The overproduction of this monoclonal immunoglobulin may be associated with either multiple myeloma or a benign monoclonal gammopathy. Despite prolonged exposure to elevated serum copper, no other tissues in the body are adversely affected by this redox metal. We describe the clinical and pathological findings in a 46-year-old woman with this disorder.

Silver nitrate injury in the rat sciatic nerve: a model of facial nerve injury

BACKGROUND

An unpublished communication of a permanent facial paralysis secondary to silver nitrate application in a postoperative mastoid cavity with a dehiscent facial nerve raises concern regarding its neurotoxicity. This study was performed to examine functional neural injury and the morphology of nerve injury due to silver nitrate contact with a peripheral motor nerve.

METHODS

Sprague-Dawley male rats were assigned to a sham surgery group or to a group where silver nitrate was applied directly to a surgically exposed sciatic nerve for 1, 5, or 10 seconds. Individual walking track data were collected on postoperative days (POD) 1, 4, 7, and 14, and the Sciatic Functional Index (SFI) was calculated to assess neural function. On POD 14, the cauterized nerve was harvested, and the histologic axon loss of each specimen was graded.

RESULTS

In all experimental groups, the most severe functional loss was noted on POD 1. At POD 14 the greatest neural recovery was observed in the 1-second group, whereas the 5- and 10-second cautery groups demonstrated a significantly worse deficit. A moderate or greater degree of axon loss was observed in 50% of animals injured for 1 second and nearly all animals injured for 5 or 10 seconds.

CONCLUSION

Functional and neuropathologic data demonstrate that silver nitrate causes significant injury to the rat sciatic nerve. A 5-second cautery causes greater functional impairment and more severe axonal loss than a 1-second injury.

Multifocal corneal argyrosis after an explosion injury

PURPOSE

To document the clinical and histopathologic corneal features of a patient who developed multifocal corneal argyrosis after a chemical explosion injury with unusual involvement of the corneal stroma and keratocytes.

METHODS

The corneal button was investigated by light and transmission electron microscopy and scanning electron microscopy combined with energy-dispersive x-ray microanalysis.

RESULTS

Clinically, the patient showed dark discoloration of the lids, periocular skin, episclera, and conjunctiva and had multiple brown dots in the superficial layers of the cornea. Microscopic examination of the cornea showed diffuse deposition of silver particles in the epithelial basement membrane, Bowman's layer, and Descemet's membrane. In the corneal stroma, silver granules accumulated intracellularly within lysosomal structures of degenerative keratocytes and extracellularly in association with collagen fibers and cellular debris. Energy-dispersive x-ray analysis showed peaks of silver and sulfur.

CONCLUSION

The toxic influence of intracellular accumulation of silver in stromal keratocytes may lead to cell damage and necrosis and result in visual impairment.

Ocular copper deposition associated with pulmonary carcinoma, IgG monoclonal gammopathy and hypercupremia. A clinicopathologic correlation

Hypercupremia with central deposition of copper in Descemet's membrane and lens capsule has been reported previously in lymphoproliferative disorders in two cases. A 60-year-old white man presented with visual acuity loss and was found to have an iridescent brown corneal and lenticular discoloration. Laboratory investigation revealed hypercupremia secondary to a poorly differentiated adenocarcinoma of the lung. Presence of copper in the eye was confirmed by specific atomic absorption spectra and histochemical stains of ocular tissue. This appears to be the first report of a carcinoma with associated hypercupremia presenting initially with ocular copper deposition.

Adverse external ocular effects of topical ophthalmic medications

Medical and pharmacologic research of recent years has led to the development of many potent and efficacious topical ophthalmic medications. Unfortunately, many of these drugs are potentially toxic or allergenic, and their adverse effects have themselves become important external ocular diseases. This paper presents a classification of these adverse effects and provides a review of their etiology, pathogenesis, histopathology, diagnosis, and management. It is hoped that this information will be helpful to ophthalmologists in their efforts to anticipate, prevent, recognize, and treat drug-induced ocular problems and that it will serve to emphasize the importance of avoiding the ill-considered use of medications.