Oncocytic cyst of the larynx: a rare finding.

A 75-year-old woman presented with an 18-month history of severe, slowly worsening dysphonia. She was a smoker and known to have multiple benign cystic thyroid lesions. She reported no associated symptoms and other medical and social history was unremarkable. Fibreoptic nasendoscopy revealed a right-sided supraglottic cyst appearing to arise from the right false vocal cord. Further bedside examination was unremarkable. She underwent microlaryngoscopy and biopsy which showed a cyst originating from the right anterior ventricle, successfully removed without rupture using cold steel. Formal histopathology revealed a 14×10×7 mm unilocular, completely excised cyst lined by oncocytic epithelium and composed of columnar cells with darkly stained nuclei and abundant granular, eosinophilic cytoplasm. Three weeks postoperatively the patient's voice had returned to normal. To date, 11 months postoperatively, there is no evidence of recurrence, and she will continue long-term follow-up.

CHORIORETINAL BIOPSY FOR THE DIAGNOSIS OF ENDOGENOUS ENDOPHTHALMITIS DUE TO ESCHERICHIA COLI.

PURPOSE: To describe the novel use of a chorioretinal biopsy technique to confirm the microbiological diagnosis of endogenous Escherichia coli (E. coli) endophthalmitis, when other investigations have been proven nondiagnostic. METHODS: Case report of an 82-year-old white man with endogenous endophthalmitis without a clearly identifiable source of infection. RESULTS: After systemic cultures and multiple aqueous and vitreous samples were unable to identify a causative organism, chorioretinal biopsy of a subretinal abscess was used to confirm the microbiological diagnosis. This ensured appropriate ophthalmic and systemic treatment of infection. CONCLUSION: Endogenous E. coli endophthalmitis is a rare and aggressive condition usually seen in patients with insulin-dependent diabetes with concurrent urinary tract infection. This case demonstrates chorioretinal biopsy to be a viable and effective method of establishing a firm microbiological diagnosis in cases of culture-negative endophthalmitis.

Malignant Transformation of Optic Nerve Melanocytoma into Melanoma Associated with Ocular Ischemic Syndrome and Oculocardiac Reflex: Case Report and Review of the Literature.

PURPOSE: To describe the clinical and pathological features of malignant transformation of an optic nerve melanocytoma over 25 years, associated with spontaneous extensive tumor necrosis, neovascular glaucoma, ocular ischemic syndrome, and oculocardiac reflex. PROCEDURES: A 60-year-old Caucasian female presented with acute severe left ocular pain and glaucoma with an intraocular pressure of 80 mmHg and bradycardia (28-40 beats/min). RESULTS: Histopathological examination of the enucleated eye showed features of malignant transformation of a spontaneously necrotic optic nerve melanocytoma associated with ocular ischemic syndrome and neovascular glaucoma. CONCLUSIONS: Yearly follow-up and awareness of possible but well-documented malignant transformation, even over several decades, is recommended. This case presents malignant transformation of an optic nerve melanocytoma associated with the common complications described in the literature over the years. Of particular interest was the development of oculocardiac reflex in this patient.

Spinal metallosis: a systematic review.

PURPOSE: To document a rarely reported complication associated with spinal instrumentation and to evaluate the current literature on spinal metallosis and spinal metalloma. METHODS: A local case report is presented. EBSCOhost, PubMed and ScienceDirect databases were used to conduct a systematic review for articles describing spinal metallosis and spinal metalloma. RESULTS: A total of 836 articles were identified using the terms "metalloma" or "metallosis". Exclusion of arthroplasty-related abstracts retrieved 46 articles of which 3 full text articles presenting spinal metalloma as a causative pathological finding responsible for neurological signs and symptoms in patients with previous spinal fusion instrumentation were reviewed. Our case is the first described with titanium-composed posterior instrumentation and fifth reported, demonstrating the phenomena of neurological symptoms and signs attributed directly to neural tissue compression by spinal metalloma after spinal instrumentation. CONCLUSION: Spinal metallosis can present weeks to years after spinal instrumentation surgery and is a potential cause of neural compression. This process appears to be independent of the instrument composition as metallosis has now been demonstrated in both titanium and stainless steel constructs.

Orbital Paraganglioma and Succinate Dehydrogenase Staining for Genetic Testing Triage and Prognosis.

PURPOSE OF THE STUDY: To describe the rare occurrence of a paraganglioma in the orbit and how to triage for genetic testing and assess the prognosis with succinate dehydrogenase subunit B (SDHB) immunohistochemical staining. METHOD: Case report. PROCEDURES: A 47-year-old 'healthy' male presented with painless exophthalmos and diplopia secondary to an infraorbital tumour mass. RESULTS: The orbital biopsy was diagnosed as paraganglioma with positive staining with SDHB. CONCLUSION: The rarity of an orbital paraganglioma was followed by the clinical search for a possible occult extraorbital primary paraganglioma. SDHB staining helped in the triage for genetic testing and gave an idea about the prognosis for this tumour.

Safety and efficacy of explanting or replacing suprachoroidal electrode arrays in a feline model.

BACKGROUND: A key requirement for retinal prostheses is the ability for safe removal or replacement. We examined whether suprachoroidal electrode arrays can be removed or replaced after implantation. METHODS: Suprachoroidal electrode arrays were unilaterally implanted into 13 adult felines. After 1 month, arrays were surgically explanted (n = 6), replaced (n = 5) or undisturbed (n = 2). The retina was assessed periodically using fundus photography and optical coherence tomography. Three months after the initial implantation, the function of replaced or undisturbed arrays was assessed by measuring the responses of the visual cortex to retinal electrical stimulation. The histopathology of tissues surrounding the implant was examined. RESULTS: Array explantation or replacement was successful in all cases. Fundus photography showed localized disruption to the tapetum lucidum near the implant's tip in seven subjects following implantation. Although optical coherence tomography showed localized retinal changes, there were no widespread statistically significant differences in the thickness of the retinal layers or choroid. The distance between the electrodes and retina increased after device replacement but returned to control values within eight weeks (P < 0.03). Staphylomas developed near the scleral wound in five animals after device explantation. Device replacement did not alter the cortical evoked potential threshold. Histopathology showed localized outer nuclear layer thinning, tapetal disruption and pseudo-rosette formation, but the overall retinal morphology was preserved. CONCLUSIONS: It is feasible to remove or replace conformable medical grade silicone electrode arrays implanted suprachoroidally. The scleral wound requires careful closure to minimize the risk of staphylomas.