New insights on the diagnosis and management of malignant tumors of the ocular surface

Tumors of the ocular surface encompass a wide spectrum of conditions involving the conjunctiva and cornea, ranging from benign lesions to life-threatening malignancies. These tumors are rare; however, they are commonly seen in the ophthalmological clinical practice as a group. The diagnosis of ocular surface tumors is mostly based on clinical evaluation of the conjunctiva and cornea and subsequent histologic confirmation. Recently, non-invasive diagnostic approaches including anterior segment high-resolution OCT (HROCT), showed promising results for their use as adjuvant for histology in case of suspicious lesions. The present review focused on the main malignant ocular surface tumors, including ocular surface squamous neoplasia (OSSN), melanocytic epithelial tumors, and conjunctival lymphoma, with the aim of discussing the epidemiological, clinical, and histopathological features, as well as to provide insights into classification and staging. In addition, the latest advances in the treatment of ocular surface tumors were reviewed, including the use of topical chemotherapy, which is gaining increasing acceptance over surgical tumor removal as it prevents surgery-related side effects and tumor recurrences

Live Demonstration:Neuromorphic Sensory Integration for Combining Sound Source Localization and Collision Avoidance

The brain is able to solve complex tasks in real time by combining different sensory cues with previously acquired knowledge. Inspired by the brain, we designed a neuromorphic demonstrator which combines auditory and visual input to find an obstacle free direction closest to the sound source. The system consists of two event-based sensors (the eDVS for vision and the NAS for audition) mounted onto a pan-tilt unit and a spiking neural network implemented on the SpiNNaker platform. By combining the different sensory information, the demonstrator is able to point at a sound source direction while avoiding obstacles in real time

Immune Response After Cochlear Implantation

A cochlear implant (CI) is an electronic device that enables hearing recovery in patients with severe to profound hearing loss. Although CIs are a successful treatment for profound hearing impairment, their effectivity may be improved by reducing damages associated with insertion of electrodes in the cochlea, thus preserving residual hearing ability. Inner ear trauma leads to inflammatory reactions altering cochlear homeostasis and reducing post-operative audiological performances and electroacoustic stimulation. Strategies to preserve residual hearing ability led to the development of medicated devices to minimize CI-induced cochlear injury. Dexamethasone-eluting electrodes recently showed positive outcomes. In previous studies by our research group, intratympanic release of dexamethasone for 14 days was able to preserve residual hearing from CI insertion trauma in a Guinea pig model. Long-term effects of dexamethasone-eluting electrodes were therefore evaluated in the same animal model. Seven Guinea pigs were bilaterally implanted with medicated rods and four were implanted with non-eluting ones. Hearing threshold audiograms were acquired prior to implantation and up to 60 days by recording compound action potentials. For each sample, we examined the amount of bone and fibrous connective tissue grown within the scala tympani in the basal turn of the cochlea, the cochleostomy healing, the neuronal density, and the correlation between electrophysiological parameters and histological results. Detection of tumor necrosis factor alpha, interleukin-6, and foreign body giant cells showed that long-term electrode implantation was not associated with an ongoing inflammation. Growth of bone and fibrous connective tissue around rods induced by CI was reduced in the scala tympani by dexamethasone release. For cochleostomy sealing, dexamethasone-treated animals showed less bone tissue growth than negative. Dexamethasone did not affect cell density in the spiral ganglion. Overall, these results support the use of dexamethasone as anti-inflammatory additive for eluting electrodes able to protect the cochlea from CI insertion trauma