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Objective: Graves' Orbitopathy (GO) has well established treatment guidelines; however, its management is still controversial. The aim was to evaluate the results of medial and mediolateral orbital decompression (OD) in intractable GO., Methods: Retrospective chart review of all patients with advanced stages of GO, who underwent medial (1-wall) or mediolateral (2-wall) OD between May 2012 and November 2014 in our institution. Ophthalmologic examinations included visual acuity, Hertel exophthalmometry (proptosis), intraocular pressure (IOP), visual field (30:2) and diplopia. Follow-up was performed 1 week, 3 months and 1 year postoperatively. Additionally, a questionnaire was used to investigate subjective benefits., Results: The study included 34 eyes of 20 patients. In our study, GO patients who underwent mediolateral OD had significantly higher IOP preoperatively (p<0.05) and lower visual acuity, proptosis and visual field compared with patients who underwent medial OD. After 1- and 2-wall OD, visual acuity, proptosis, visual field and IOP in upgaze improved significantly. Using a questionnaire, the patients reported significant improvements in impaired vision, eye pain and pressure, vitality and social life. 94% of all patients reported they would repeat the operation. After 2-wall OD, the surgical scar had little effect., Conclusion: With GO patients in advanced stages, both medial (1-wall) and mediolateral (2-wall) OD procedures are convincing therapeutic options. In more advanced GO stages with high IOP, 2-wall OD should be prioritized, as mediolateral OD had superior long-term functional outcomes., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

The auditory midbrain implant (AMI), which is designed for stimulation of the inferior colliculus (IC), is now in clinical trials. The AMI consists of a single shank array (20 contacts) and uses a stimulation strategy originally designed for cochlear implants since it is already approved for human use and we do not yet know how to optimally activate the auditory midbrain. The goal of this study was to investigate the effects of different pulse rates and phase durations on loudness and pitch percepts because these parameters are required to implement the AMI stimulation strategy. Although each patient was implanted into a different region (i.e. lateral lemniscus, central nucleus of IC, dorsal cortex of IC), they generally exhibited similar threshold versus phase duration, threshold versus pulse rate, and pitch versus pulse rate curves. In particular, stimulation with 100 mus/phase, 250 pulse per second (pps) pulse trains achieved an optimal balance among safety, energy, and current threshold requirements while avoiding rate pitch effects. However, we observed large differences across patients in loudness adaptation to continuous pulse stimulation over long time scales. One patient (implanted in dorsal cortex of IC) even experienced complete loudness decay and elevation of thresholds with daily stimulation. Comparing these results with those of cochlear implant and auditory brainstem implant patients, it appears that stimulation of higher order neurons exhibits less and even no loudness summation for higher rate stimuli and greater current leakage for longer phase durations than that of cochlear neurons. The fact that all midbrain regions we stimulated, which includes three distinctly different nuclei, exhibited similar loudness summation effects (i.e. none for pulse rates above 250 pps) suggests a possible shift in some coding properties that is affected more by which stage along the auditory pathway rather than the types of neurons are being stimulated. However, loudness adaptation occurs at multiple stages from the cochlea up to the midbrain.