Radiologically isolated syndrome – incidental magnetic resonance imaging findings suggestive of multiple sclerosis, a systematic review

Abstract

With increasing availability of magnetic resonance imaging (MRI), there is also an increase in incidental abnormal findings. MRI findings suggestive of multiple sclerosis in persons without typical multiple sclerosis symptoms and with normal neurological findings are defined as radiologically isolated syndrome (RIS). Half of the persons with RIS have their initial MRI because of headache, and some have a subclinical cognitive impairment similar to that seen in multiple sclerosis. Radiological measurements also show a similarity between RIS and multiple sclerosis. Approximately two-thirds of persons with RIS show radiological progression and one-third develop neurological symptoms during mean follow-up times of up to five years. Cervical cord lesions are important predictors of clinical conversion. Management has to be individualised, but initiation of disease modifying therapy is controversial and not recommended outside of clinical trials since its effects have not been studied in RIS. Future studies should try to establish the prevalence and long-term prognosis of RIS, its impact on quality of life, and define the role of disease modifying therapy in RIS.

Evoked potentials and other guiding factors of conversion from radiologically isolated syndrome to definite multiple sclerosis

“…None of the patients admitted in the RIS phase, which is included in our study were receiving a conventional MS treatment. Most common complaint among the RIS patients was identified to be headache in various studies as found in this study (1,5,10).…”

“…Approximately in two-thirds of the patients develop radiographic progression within the first 5 years. When the number of lesions in the MRI is high (> 9), gadolinium (Gd) enhancement of the asymptomatic lesions is present and in particular if cervical cord lesions are seen, clinical conversion rate is higher (2,5,6,7,17,18,19). In our study, 8 of 49 patients had subsequent neurological episodes during the follow-up period, and thus began to be followed by a diagnosis of Clinically Isolated Syndrome (CIS) -MS accordingly.…”

“…(5,7,8,9). None of the patients admitted in the RIS phase, which is included in our study were receiving a conventional MS treatment.…”

Management of Intracranial Incidental Findings on Brain MRI

“…40 % of these patients develop neurological symptoms, and 10 % will formally meet the diagnostic criteria for multiple sclerosis [31]. Detected asymptomatic myelon lesions increases the risk of developing symptoms [32]. As a rule, patients who eventually develop a neurological deficit also exhibit a progression of lesions in T2w and FLAIR images.…”

“…As a rule, patients who eventually develop a neurological deficit also exhibit a progression of lesions in T2w and FLAIR images. Although there is no current consensus regarding the type and extent of possible therapy [32], a neurological work-up should be performed (Category II).…”