Purpose: We assessed the safety and efficacy of a technically advanced subretinal electronic implant, RETINA IMPLANT Alpha AMS, in end stage retinal degeneration in an interim analysis of two ongoing prospective clinical trials. The purpose of this article is to describe the interim functional results (efficacy).Methods: The subretinal visual prosthesis RETINA IMPLANT Alpha AMS (Retina Implant AG, Reutlingen, Germany) was implanted in 15 blind patients with hereditary retinal degenerations at four study sites with a follow-up period of 12 months (www.clinicaltrials.gov NCT01024803 and NCT02720640). Functional outcome measures included (1) screen-based standardized 2- or 4-alternative forced-choice (AFC) tests of light perception, light localization, grating detection (basic grating acuity (BaGA) test), and Landolt C-rings; (2) gray level discrimination; (3) performance during activities of daily living (ADL-table tasks).Results: Implant-mediated light perception was observed in 13/15 patients. During the observation period implant mediated localization of visual targets was possible in 13/15 patients. Correct grating detection was achieved for spatial frequencies of 0.1 cpd (cycles per degree) in 4/15; 0.33 cpd in 3/15; 0.66 cpd in 2/15; 1.0 cpd in 2/15 and 3.3 cpd in 1/15 patients. In two patients visual acuity (VA) assessed with Landolt C- rings was 20/546 and 20/1111. Of 6 possible gray levels on average 4.6 ± 0.8 (mean ± SD, n = 10) were discerned. Improvements (power ON vs. OFF) of ADL table tasks were measured in 13/15 patients. Overall, results were stable during the observation period. Serious adverse events (SAEs) were reported in 4 patients: 2 movements of the implant, readjusted in a second surgery; 4 conjunctival erosion/dehiscence, successfully treated; 1 pain event around the coil, successfully treated; 1 partial reduction of silicone oil tamponade leading to distorted vision (silicon oil successfully refilled). The majority of adverse events (AEs) were transient and mostly of mild to moderate intensity.Conclusions: Psychophysical and subjective data show that RETINA IMPLANT Alpha AMS is reliable, well tolerated and can restore limited visual functions in blind patients with degenerations of the outer retina. Compared with the previous implant Alpha IMS, longevity of the new implant Alpha AMS has been considerably improved. Alpha AMS has meanwhile been certified as a commercially available medical device, reimbursed in Germany by the public health system.

Although it has been shown that different mouse strains may have differently large eyes, the present study shows that a specific gene knockout can produce relative myopia, compared with the wild-type with near-identical genetic background. Further experiments are needed to determine whether the observed effects of Egr-1 deletion are due to changes in function within the retina or other ocular tissues or to changes of function in other systems that may affect ocular growth from outside the eye.

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There is extensive local compensation of imposed refractive errors in chickens. For the tested hole sizes, peripherally imposed defocus did not influence central refractive development. To alter central refractive development, the unobstructed part in the central visual field may have to be quite small (hole sizes smaller than 4mm, with the lenses at a vertex distance of 2-3mm).

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Bromocriptine (1.25 mg BID) was administered orally to a 23 year old asymptomatic female with accelerated growth and a parasellar tumor (tissue type unknown). Other forms of therapy were refused. Length increased from 76 to 95 cm (22 cm/yr) and weight increased from 10 to 16.25 kg between ages 13 and 23 months. Bone age was 2 years at a chronolorical age of 18 months. Somatomedin C level was 4.3 Ulml (n=2: normal 0.8 to 2.2 Ulml). Thirteen growth hormone values during overnight monitoring averaged 4.7 ng/ml, range 1.8 to 7.9 ng/ml. Suppression to 5.0 nglml was seen during an OGTT. Other neuroendocrine functions were normal. No evidence of isosexual precocity was noted. Somatomedin C levels were 3.2, 2.6, 2.5. 2.4, and 2.2 U/ml on days 1 to 5 of therapy, 2.5 Ulml at 14 days and 2.7 Ulml at 56 days. Length increased from 95 to 97 cm (4.8 cm/ yr) during the first 5 months of therapv. CT scan at 5 months shows no change in tumor size. The patient remains asymptomatic.The decrease in levels of somatomedin C associated with a reduction in the growth rate may have resulted from decreased GH oroduction; however. other effects of bromocriptine, such as blockinr the peripheral action of somatomedins may be involved. In rats permanent stunting follows neonatal head-irradiation (Head-X); during the post-weaning period full catch-up growth (CU) occurs after fasting (F); failure of CU occurs after cortisone treatment (C); and superimposition of F or C on Head-X results in similar responses in the stunting after Head-X. In this study growth hormone (GH) secretory profiles were determined in rats treated with Head-X, F or C. Superior vena cava blood was sampled at 15 min intervals during the light phase in chronically cannulated undisturbed animals. Sampling duration was 9 h in Head-X, 6 h in F, and 12 h in C. The results, ex- EXPEBIYENTAL EVIDEKCE FOR CENTRAL NERVOUS SYSTEFI COKTROLS(13) 98.4t11.9 (16) 84.6~10.9 (7) 55.3C7.4 P <0.025 ~'3.05 ~0.025 Normal pulsatile GH rhythm existed in all three models. The data indicate that GH controls are linked to the CU control. That GH secretion is decreased in Head-X is conpatible with the concept that brain injury has reset growth controls for a smaller body size. We conclude that CH release is linked to the putative CU control through a mechanism which senses the discrepancy between actual body size and normal body size for age.