Mydriasis disorders e.g. epilepsy, stroke, and impending brain herniation are known to lead to temporal mydriasis as well. A brain catastrophe, or a rapidly increasing brain mass, can cause compression of the oculomotor nerve. In cases of head injury or orbit trauma (eye injury), the iris sphincter (the muscle responsible for closing the pupil) or the nerves controlling it can be damaged, reducing or eliminating the normal pupillary light reflex. A mydriatic is an agent that induces dilation of the pupil. Drugs such as tropicamide are used in medicine to permit examination of the retina and other deep structures of the
Widening (computer science) try to reason about abstract states, which correspond to many concrete states. Often, the abstract states are structured in such a way that by repeatedly following the effect of program steps or by coarsening the abstraction, one obtains a chain of abstractions that is proven to terminate. Widening techniques and the closely related "acceleration" techniques are used in the "forward analysis" of systems in the discipline of symbolic model checking. The techniques detect cycles, i.e. sequences of abstract state transitions that could be repeated. When such a sequence can be repeated over and over, yielding new states (e.g. a variable