Epithelial downgrowth. Report of 2 cases diagnosed by ocular biopsy.

Epithelial downgrowth is an uncommon complication of ocular surgery or adverse consequence of accidental trauma, caused by surface squamous epithelium that has gained access to the inner compartments of the eye. Once embedded in the eye, squamous epithelium spreads over contiguous structures, interfering with normal aqueous outflow and vision. The pursuit of improved therapies is ongoing, but the greatest chance of preventing blindness is with early recognition. Two cases of epithelial downgrowth diagnosed from a corneal button and an iris biopsy are presented to familiarize pathologists with this disorder. In the appropriate clinical setting, the presence of stratified squamous epithelium, with or without goblet cells, is diagnostic of epithelial downgrowth. Other than congenital epithelial inclusion cyst (choristoma), stratified squamous epithelium is not found inside the eye. Surface epithelium introduced surgically or traumatically needs to be differentiated histologically from ectopic corneal endothelium and metastatic carcinoma.

Horse to human: Streptococcus equi septicemia presenting as endogenous endophthalmitis.

Purpose: To present a rarely reported systemic infection with streptococcus equi subspecies zooepidemicus (streptococcus equi), transmitted from a horse, and to describe successful treatment when complicated by endogenous endophthalmitis. Observations: We diagnosed suspected streptococcus equi septicemia presenting as loss of vision in the right eye of an otherwise healthy polo player/horse trainer. He received immediate intravenous antibiotics and three vitrectomies with two intravitreal antibiotic injections during the first week, to cure infection and subsequent retinal detachment. Blood and initial vitreous cultures rapidly grew streptococcus equi. The septicemia was quickly controlled by systemic antibiotics without developing commonly seen and often fatal meningitis. The right eye recovered 20/30 visual acuity three months post infection. Conclusions: Presentation of this rare septicemia as endogenous endophthalmitis illustrates the potentially lifesaving role of early diagnosis by the ophthalmologist. Immediate and recurrent vitrectomy in conjunction with intravitreal and systemic antibiotic therapy resulted in recovery of near normal vision, whereas less timely and interventional treatments have failed heretofore.

Monthly Versus Treat-and-Extend Ranibizumab for Diabetic Macular Edema: A Prospective, Randomized Trial.

BACKGROUND AND OBJECTIVE: Compare fixed monthly dosing of ranibizumab to treat-and-extend (T&E) ranibizumab during a period of 24 months for diabetic macular edema (DME) treatment. PATIENTS AND METHODS: Single-center, randomized, prospective pilot study that included 20 eyes of 20 subjects. Patients' best-corrected visual acuity (BCVA) was less than or equal to 20/40 and central foveal thickness on spectral-domain optical coherence tomography was greater than 325 µm. Intravitreal ranibizumab was dosed monthly or by protocol-specified treat-and-extend. Primary outcome was mean change in mean BCVA. Institutional review board approval was obtained. RESULTS: At month 24 (M24), there was a mean 8.3-letter gain in the monthly treatment group and an 8.5-letter gain in the T&E group (P = .082; 90% confidence interval). The average change from baseline BCVA was not statistically significantly different at any timepoint. At M24, the median number of injections in the monthly and T&E groups were 22.5 and 18.5, respectively (P = .287). CONCLUSIONS: Visual acuity with monthly dosing appears equivalent to T&E dosing during the course of 24 months. There was a trend toward a lower injection burden in the T&E arm. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:e191-e197.].

Pathology of Ischemic Optic Neuropathy.

Ischemic optic neuropathy (ION) describes a state of hypoxic injury of the optic nerve. Clinically, ION is divided into anterior and posterior forms defined by the presence or absence of optic disc swelling, respectively. It is further classified as arteritic when secondary to vasculitis, and nonarteritic when not. The site of vascular occlusion for anterior ION from giant cell arteritis is the short posterior ciliary arteries, but mechanical vascular obstruction does not play a role in most nonarteritic cases. Histologically, ION is characterized by axon and glial necrosis, edema, and a sparse mononuclear response. Like other ischemic injuries, the morphologic alternations in the nerve are time dependent. A variant of ION called cavernous degeneration (of Schnabel) features large cystic spaces filled with mucin. Several conditions can histologically mimic cavernous degeneration of the optic nerve. The scarcity of cases of ION examined histologically has contributed to an incomplete understanding of its pathogenesis.