Higher sensitivity for traumatic cerebral microbleeds at 7 T ultra-high field MRI: is it clinically significant for the acute state of the patients and later quality of life?

Abstract

Background: The present study evaluates the possible prognostic benefits of 7 T susceptibility weighted imaging (SWI) of traumatic cerebral microbleeds (TMBs) over 3 T SWI to predict the acute clinical state and subjective impairments, including health-related quality of life (HRQOL), after closed head injury (CHI). Methods: The study group comprised 10 participants with known TMBs All subjects underwent 3 T magnetic resonance imaging (MRI) and 7 T MRI, respectively. Location and count of TMBs were independently evaluated by two neuroradiologists. The initial Glasgow Coma Scale (GCS), the duration of coma and further clinical data were taken from the patients records. HRQOL was assessed by means of a questionnaire. Memory complaints and neurological symptoms were inquired at the time of the MRI examinations. Results: SWI revealed a total of 485 TMBs at 3 T, 584 TMBs at 7 T with similar spatial resolution, and 684 TMBs at 7 T with a factor of 10 higher spatial resolution. The TMBs depicted by 7 T high-resolution SWI were correlated with the duration of coma (Spearman’s rho of 0.77). The corresponding association with TMBs in 3 T MRI SWI showed a Spearman’s rho of 0.71. The initial GCS score and TMBs correlated with a Spearman’s rho of −0.35 at 3 T SWI MRI and a rho of −0.33 at 7 T high-resolution SWI, respectively. The physical aspect of HRQOL correlated substantially with the count of TMBs (rho = 0.44 for 3 T SWI and rho = 0.35 for both 7 T SWI sequences, respectively). Conclusions: The number of TMBs showed a substantial association with indicators of the acute clinical state and chronic neurobehavioral parameters after CHI, but there was no additional advantage of 7 T MRI. These preliminary findings warrant a larger prospective study for the future.

A Systematic Review evaluating the role of the 7 T MRI in Neurosurgery: Unveiling Trends in the Literature So Far after Clinical Approval in 2017

“…The number of traumatic cerebral microbleeds showed a substantial association with indicators of the acute clinical state and chronic neurobehavioral parameters after closed head injury, but there was no additional advantage of 7 T MRI. These preliminary findings warrant a larger prospective study for the future [37]. The number of TMBs showed a substantial association with indicators of the acute clinical state and chronic neurobehavioral parameters after CHI, but there was no additional advantage of 7 T MRI.…”

Susceptibility-Weighted MRI and Microbleeds in Mild Traumatic Brain Injury: Prediction of Posttraumatic Complaints?

“…We describe 11 3T studies of SWI in mTBI in detail (Table 1). In 5 studies, SWI was performed in the early posttraumatic phase (<1 month) [27,[33][34][35][36], in 3 in the late phase [15,37,38], and 3 studies were longitudinal [12,39,40]. Most studies were prospective cohort or case-control studies.…”

“…Studies using 3T SWI are able to show much smaller microbleeds, especially when longer echo times are used. Ultra-high field 7T MRIs detect even smaller and more microbleeds, however at the cost of increased artifacts [24, 26, 27]. In this paper, we will only review 3T and 1.5T SWI studies, as these field strengths are available in everyday practice.…”

Neuroimaging at 7 Tesla: a pictorial narrative review

“…In another study, the total number of traumatic CMBs in 10 patients were 485 and 584 using SWI at 3T and 7T, respectively with a similar spatial resolution. The number of observed lesions increased to 684 at 7T when a higher spatial resolution was used (185). Radiation therapy is associated with CMBs in brain tumors (186).…”