Pilot study of a glue-less, suture-less amniotic membrane for pterygium excision.

PURPOSE: Pterygium is a non-cancerous, fibrovascular growth of the bulbar conjunctiva that can cause visual disturbance, ocular pain, and cosmetic concerns. Surgical management is required in certain cases, which consists of excising the pterygium and associated Tenon's, then overlaying the bare sclera with an autograft or amniotic membrane using glue or sutures. The purpose of this study is to assess outcomes of pterygium repair using a newly developed self-adhesive amniotic membrane that does not require glue or sutures for fixation. METHODS: Chart review of pterygium excision using a new self-adhesive amniotic membrane from a single surgical practice from 2012-2018. Descriptive statistics from 51 primary cases of pterygium excision were included. RESULTS: Pterygium recurrence occurred in 3 of the 51 self-adhesive amniotic membrane cases studied, resulting in a recurrence rate of 5.9%. Pterygium excision with the self-adhesive amniotic membrane had high rate of pyogenic granuloma formation of 27%. Self-adhesive amniotic membranes were found to perform comparably to more widely used techniques for pterygium excision, namely amniotic membranes and conjunctival autographs with glue or sutures. However, the self-adhesive grafts are associated with substantially more pyogenic granuloma formation. CONCLUSION: Self-adhesive amniotic membranes offer comparable efficacy for preventing pterygium recurrence in comparison to other amniotic membranes and the conjunctival autograft. The incidence of pyogenic granuloma formation is higher in self-adhesive grafts compared to other widely used options.

A Rare Presentation of Direct Traumatic Optic Neuropathy in a Patient Poked in the Eye by an Antenna.

Traumatic optic neuropathy (TON) is defined as a loss of vision due to a traumatic injury to the optic nerve. Numerous mechanisms may contribute to the development of TON; however, most cases involve injuries to the globe, orbit, or adnexa. This case report presents a 24-year-old male who was inadvertently poked in the eye with an antenna and developed a direct optic nerve injury in the absence of a significant injury to the surrounding orbital structures. A CT scan was used to confirm the diagnosis. No visual recovery was observed throughout his clinical course. The proposed pathophysiologic mechanisms, clinical presentation, complications, treatments, and prognosis of traumatic optic neuropathy are subsequently discussed.

Traumatic central retinal vein occlusion following a hawk attack to the posterior cranium.

PURPOSE: We describe a patient who developed a central retinal vein oculsion following a diving hawk attack to her posterior cranium. OBSERVATIONS: A 50-year-old female presented with decreased visual acuity and color perception in the left eye following a diving hawk attack to her right-posterior parietal cranium. Medical history was significant for well-controlled type 2 diabetes, hyperlipidemia, and obesity. Fundoscopy of the left eye revealed pre, intra and subretinal hemorrhages in all 4 quadrants consistent with the "blood and thunder" appearance. Additional findings included optic disk edema, venous dilation and tortuosity. Optical Coherence Tomography of the left eye demonstrated pronounced macular edema with intra and subretinal fluid accumulation. Pattern electroretinography of the left eye was flattened. CONCLUSIONS AND IMPORTANCE: There are few documented cases of central retinal vein occlusion following blunt trauma to the cranium in the literature. To the best of our knowledge, this is the first case of central retinal vein occlusion associated with posterior cranial trauma. Also unique to the case is the mechanism of injury whereby the patient was attacked by a hawk at a high-diving velocity.

Kinetics of CO+ and CO2+ with N and O atoms.

We have measured reaction rate constants for CO+ and CO2+ reacting with N and O atoms using a selected ion flow tube apparatus equipped with a microwave discharge atom source. Experimental work was supplemented by molecular structure calculations. Calculated pathways show the sensitivity of kinetic barriers to theoretical methods and imply that high-level ab initio methods are required for accurate energetics. We report room-temperature rate constants of 1.0 ± 0.4 × 10-11 cm3 s-1 and 4.0 ± 1.6 × 10-11 cm3 s-1 for the reactions of CO+ with N and O atoms, respectively, and 8.0 ± 3.0 × 10-12 cm3 s-1 and 2.0 ± 0.8 × 10-11 cm3 s-1 for the reactions of CO2+ with N and O atoms, respectively. The reaction of CO2+ + O is observed to yield O2+ exclusively. These values help resolve discrepancies in the literature and are important for modeling of the Martian atmosphere.