Can T2 blackout effect be a marker of iron accumulation in brains of multiple sclerosis patients?

Abstract

<jats:sec><jats:title>Objective:</jats:title><jats:p> T2 blackout (TBO) effect, which is a common finding in the brains of multiple sclerosis (MS) patients and older population that are imaged for other reasons on diffusion weighted imagings (DWI) and apparent diffusion coefficient (ADC) map show the existence of paramagnetic materials in the tissue. Because iron is known to accumulate in especially deep gray matter (DGM) structures in MS brains, we aimed to investigate the relationship between TBO and clinico-radiological parameters that may be iron-related in MS. </jats:p></jats:sec><jats:sec><jats:title>Methods:</jats:title><jats:p> We retrospectively reviewed the latest MR images of MS patients on 3 Tesla MR scanner between 2018 and 2019. TBO existence and severity on DWI–ADC was assessed by two radiologists and its correlation with several outcomes of MS was investigated. </jats:p></jats:sec><jats:sec><jats:title>Results:</jats:title><jats:p> No significant relationship was found between TBO and gender, subtype of MS whereas TBO was positively correlated with parameters such as black-hole lesions, cortical atrophy, duration of disease, age and extended disability status scale (EDSS) score. </jats:p></jats:sec><jats:sec><jats:title>Conclusions:</jats:title><jats:p> TBO shows correlation with the conditions which were revealed to be associated with iron accumulation in the brain of MS patients in the literature. Therefore, we concluded that TBO and its severity in DGM may represent iron accumulation in MS brains. </jats:p></jats:sec><jats:sec><jats:title>Advances in knowledge:</jats:title><jats:p> TBO effect as a frequent imaging finding in daily practice may be used as predictor of the disease course of MS due to possible effects of iron accumulation in brain and thereby may be useful in modifying treatment strategies. </jats:p></jats:sec>

Case report: Ventricular primary central nervous system lymphoma with partial hypointensity on diffusion-weighted imaging

“…TBO, as the opposite of T2 shines through, is a less described effect that reflects the T2 shortening due to paramagnetic substances on DWI. Because DWI primarily is a T2-weighted sequence, T2 changes in tissue may have an influence on DWI (15)(16)(17). Exactly, our lesion in the third ventricle is extremely low intensity on T2WI.…”

Magnetic resonance imaging features of presumed intracerebral hemorrhages in dogs show a significant association between apparent diffusion coefficient peripheral layer and estimated bleeding age and commonly exhibit a T2 blackout effect

“…[6][7][8] In the majority of these conditions the reason behind the presence of T2 BOE is supposed to be intralesional hemorrhage, but in some diseases, the accumulation of other paramagnetic substances, responsible for the phenomenon, can play a role. [6][7][8] In brain abscesses there is often a T2 hypointense rim, probably due to paramagnetic free radicals released from macrophages, while in senile people and in patients with multiple sclerosis the deposition of iron could cause similar results. [7][8][9][10][11][12][13][14] In dogs T2 BOE was only reported in one study, where it was detected during the chronic stage of intracerebral hemorrhage, while T2 shine-through was more commonly found in the early subacute stage.…”

“…[6][7][8] In brain abscesses there is often a T2 hypointense rim, probably due to paramagnetic free radicals released from macrophages, while in senile people and in patients with multiple sclerosis the deposition of iron could cause similar results. [7][8][9][10][11][12][13][14] In dogs T2 BOE was only reported in one study, where it was detected during the chronic stage of intracerebral hemorrhage, while T2 shine-through was more commonly found in the early subacute stage. 4 In cats this phenomenon has recently been described in fungal granulomas caused by central nervous system blastomycosis.…”

“…It is the opposite of the T2 shine‐through phenomenon, which instead describes the substantial contribution of T2 hyperintensity observed on DWI. In human medicine, T2 BOE has been described in the acute and early subacute stages of intracranial hematomas as well as in other pathologies, such as brain abscesses, toxoplasmosis, aspergillosis, or metastatic lesions 6–8 . In the majority of these conditions the reason behind the presence of T2 BOE is supposed to be intralesional hemorrhage, but in some diseases, the accumulation of other paramagnetic substances, responsible for the phenomenon, can play a role 6–8 .…”

“…In human medicine, T2 BOE has been described in the acute and early subacute stages of intracranial hematomas as well as in other pathologies, such as brain abscesses, toxoplasmosis, aspergillosis, or metastatic lesions 6–8 . In the majority of these conditions the reason behind the presence of T2 BOE is supposed to be intralesional hemorrhage, but in some diseases, the accumulation of other paramagnetic substances, responsible for the phenomenon, can play a role 6–8 . In brain abscesses there is often a T2 hypointense rim, probably due to paramagnetic free radicals released from macrophages, while in senile people and in patients with multiple sclerosis the deposition of iron could cause similar results 7–14 .…”