Radiologically isolated syndrome (RIS) is a clinical situation in which a person has white matter lesions suggestive of multiple sclerosis (MS), as shown on an MRI scan that was done for reasons unrelated to MS symptoms. The nerve lesions in these people show dissemination in space with an otherwise normal neurological examination and without historical accounts of typical MS symptoms.MRI findings that are consistent with multiple sclerosis have been observed in healthy people who underwent MRI scanning, and 50% go on to develop symptomatic MS, sometimes with a primary progressive course. This condition was first characterized in 2009. Diagnosis
The criteria for an RIS diagnosis are as follows:
The presence of incidental MRI findings in the CNS white matter:
Ovoid and well-circumscribed homogeneous foci, with or without involvement of the corpus callosum
T2 hyperintensities larger than 3 mm in diameter, which fulfill at least 3 of the 4 Barkhof MRI criteria for DIS
The CNS abnormalities are not consistent with a vascular condition
No historical accounts of clinical symptoms consistent with neurological dysfunction. MRI anomalies do not account for apparent impairment in social, occupational, or generalized areas of functioning. MRI anomalies are not due to substance abuse, such as recreational drug use, toxic exposure, or a prior known medical condition. Exclusion of a differential diagnosis of leukoaraiosis, or extensive white matter pathology excluding the corpus callosum. MRI anomalies of the CNS are not accounted for by another disease. Discovery
RIS is discovered when an MRI scan is performed for other reasons.
Vibegron, sold under the brand name Gemtesa, is a medication for the treatment of overactive bladder.Vibegron (other names: RVT-901; MK4618; KRP114V; URO-901) is a selective beta 3 adrenergic receptor agonist. The most common side effects include headache, urinary tract infection, common cold, diarrhea, nausea, and upper respiratory tract infection.It was approved for medical use in the United States in December 2020. Medical uses
Vibegron is indicated for the treatment of overactive bladder with symptoms of urge urinary incontinence, urgency, and urinary frequency in adults. History and Discovery
The beta 3 adrenergic receptor was discovered in the late 1980s and initially beta3AR agonists were investigated as treatment for obesity and diabetes. A number of compounds were tested in clinical trials but didnt show sufficient benefits in these areas.Since the 2000s there is evidence that there are beta3AR on the detrusor muscle of the bladder. The detrusor muscle contracts during urination and remains relaxed to allow the bladder to store urine. Mirabegron was the first FDA approved selective agonist approved to treat overactive bladder (OAB).Vibegron is a selective beta3AR agonist that is developed in Japan by Kyorin Pharmaceutical Co., Ltd and Kissei Pharmaceutical Co.,Ltd and Urovant Sciences to treat overactive bladders  and pain caused by irritable bowel syndrome.