However, in some other patients, the character of the emotional display can be incongruent with, and even contradictory to, the emotional valence of the provoking stimulus or may be incited by a stimulus with no clear valence. For example, a patient may laugh in response to sad news or cry in response to stimuli with no emotional undertone, or, once provoked, the episodes may switch from laughing to crying or vice versa.The symptoms of PBA can be severe, with persistent and unremitting episodes. Characteristics include:

The onset can be sudden and unpredictable, and has been described by some patients as coming on like a seizure;
The outbursts have a typical duration of a few seconds to several minutes; and,
The outbursts may happen several times a day.Many people with neurologic disorders exhibit uncontrollable episodes of laughing, crying, or anger that are either exaggerated or contradictory to the context in which they occur. Where patients have significant cognitive deficits (e.g., Alzheimers) it can be unclear whether it is true PBA as opposed to a grosser form of emotional dysregulation, but patients with intact cognition often report the symptom as disturbing. Patients report that their episodes are at best only partially amenable to voluntary control, and unless they experience a severe change of mental status, as in traumatic brain injury they often have insight into their problem and judge their emotional displays as inappropriate and out of character.
Retinal tears are closed by laser treatment or cryotherapy, and detached retinas are reattached surgically.Even after treatment, it can take months for the body to clear all of the blood from the vitreous. In cases of vitreous hemorrhage due to detached retina, long-standing vitreous hemorrhage with a duration of more than 2–3 months, or cases associated with rubeosis iridis or glaucoma, a vitrectomy may be necessary to remove the standing blood in the vitreous. References


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