Objectives: Little is known about the very long-term cognitive outcome in patients with childhood-onset epilepsy. The aim of this unique prospective population-based cohort study was to examine cognitive outcomes in aging participants with childhood-onset epilepsy (mean onset age=5.3 years) five decades later (mean age at follow-up=56.5 years).Methods: The sample consisted of 48 participants with childhood-onset epilepsy and 48 age-matched healthy controls aged 48–63 years. Thirty-six epilepsy participants were in remission and 12 continued to have seizures. Cognitive function was examined with 11 neuropsychological tests measuring language and semantic function, episodic memory, and learning, visuomotor function, executive function, and working memory. Results: The risk of cognitive impairment was very high in participants with continuing seizures; odds ratio (OR)=11.7 (95% confidence interval [CI] (2.8, 49.6), p=.0008). They exhibited worse performances across measures of language and semantic function, and visuomotor function compared to participants with remitted epilepsy and healthy controls. In the participants with remitted epilepsy, the risk of cognitive impairment was somewhat elevated, but not statistically significant; OR=2.6 (95% CI [0.9, 7.5], p=.08).Conclusions: Our results showed that the distinction of continued versus discontinued seizures was critical for determining long-term cognitive outcome in childhood-onset epilepsy. Few participants in remission exhibited marked cognitive impairment compared to age-matched peers. However, a subgroup of participants with decades long active epilepsy, continuous seizure activity and anti-epileptic drug (AED) medication, showed clinically significant cognitive impairment and are thus in a more precarious position when entering older age. (JINS, 2017, 23, 332–340)

The interdependence of the development of the eye and oculomotor system during embryogenesis is currently unclear. The occurrence of clinical anophthalmia, where the globe fails to develop, permits us to study the effects this has on the development of the complex neuromuscular system controlling eye movements. In this study, we use very high-resolution T2-weighted imaging in five anophthalmic subjects to visualize the extraocular muscles and the cranial nerves that innervate them. The subjects differed in the presence or absence of the optic nerve, the abducens nerve, and the extraocular muscles, reflecting differences in the underlying disruption to the eye’s morphogenetic pathway. The oculomotor nerve was present in all anophthalmic subjects and only slightly reduced in size compared to measurements in sighted controls. As might be expected, the presence of rudimentary eye-like structures in the socket appeared to correlate with development and persistence of the extraocular muscles in some cases. Our study supports in part the concept of an initial independence of muscle development, with its maintenance subject to the presence of these eye-like structures.

Two types of centrifugal pathways to the retina have been found in the vertebrates, according to the location of the cell bodies and presence or absence of connections with the optic tectum. One type is represented by the isthmo-optic nucleus (ION) of birds and, therefore, termed “ION-type” retinopetal system. The other type is termed “non-ION-type” retinopetal system. The ION-type retinopetal systems have been found in the cyclostomes, teleosts, reptiles, and birds. This review describes the anatomy and physiology of the ION-type retinopetal systems, mainly of birds and teleosts. On the basis of anatomical and physiological evidence cited in this review, the ION-type retinopetal systems can be regarded as the tectofugal pathways to the retina. The function of the ION-type retinopetal systems is discussed in detail, with special emphasis on their relation to the role of the tectum in mediating visuomotor behavior.